Move json errors over to gmsl (#3080)

109 files changed, 808 insertions, 1217 deletions

diff --git a/clientapi/auth/auth.go b/clientapi/auth/auth.go
index 93345f4b..479b9ac7 100644
--- a/clientapi/auth/auth.go
+++ b/clientapi/auth/auth.go
@@ -23,8 +23,8 @@ import (
 	"net/http"
 	"strings"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -58,7 +58,7 @@ func VerifyUserFromRequest(
 	if err != nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.MissingToken(err.Error()),
+			JSON: spec.MissingToken(err.Error()),
 		}
 	}
 	var res api.QueryAccessTokenResponse
@@ -68,21 +68,21 @@ func VerifyUserFromRequest(
 	}, &res)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("userAPI.QueryAccessToken failed")
-		jsonErr := jsonerror.InternalServerError()
+		jsonErr := spec.InternalServerError()
 		return nil, &jsonErr
 	}
 	if res.Err != "" {
 		if strings.HasPrefix(strings.ToLower(res.Err), "forbidden:") { // TODO: use actual error and no string comparison
 			return nil, &util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden(res.Err),
+				JSON: spec.Forbidden(res.Err),
 			}
 		}
 	}
 	if res.Device == nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.UnknownToken("Unknown token"),
+			JSON: spec.UnknownToken("Unknown token"),
 		}
 	}
 	return res.Device, nil
diff --git a/clientapi/auth/login.go b/clientapi/auth/login.go
index 5467e814..77835614 100644
--- a/clientapi/auth/login.go
+++ b/clientapi/auth/login.go
@@ -21,9 +21,9 @@ import (
 	"net/http"
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/setup/config"
 	uapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -37,7 +37,7 @@ func LoginFromJSONReader(ctx context.Context, r io.Reader, useraccountAPI uapi.U
 	if err != nil {
 		err := &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Reading request body failed: " + err.Error()),
+			JSON: spec.BadJSON("Reading request body failed: " + err.Error()),
 		}
 		return nil, nil, err
 	}
@@ -48,7 +48,7 @@ func LoginFromJSONReader(ctx context.Context, r io.Reader, useraccountAPI uapi.U
 	if err := json.Unmarshal(reqBytes, &header); err != nil {
 		err := &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Reading request body failed: " + err.Error()),
+			JSON: spec.BadJSON("Reading request body failed: " + err.Error()),
 		}
 		return nil, nil, err
 	}
@@ -68,7 +68,7 @@ func LoginFromJSONReader(ctx context.Context, r io.Reader, useraccountAPI uapi.U
 	default:
 		err := util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue("unhandled login type: " + header.Type),
+			JSON: spec.InvalidParam("unhandled login type: " + header.Type),
 		}
 		return nil, nil, &err
 	}
diff --git a/clientapi/auth/login_test.go b/clientapi/auth/login_test.go
index c91cba24..eb87d5e8 100644
--- a/clientapi/auth/login_test.go
+++ b/clientapi/auth/login_test.go
@@ -21,11 +21,11 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/userutil"
 	"github.com/matrix-org/dendrite/setup/config"
 	uapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -140,7 +140,7 @@ func TestBadLoginFromJSONReader(t *testing.T) {
 				"type": "m.login.invalid",
 				"device_id": "adevice"
             }`,
-			WantErrCode: "M_INVALID_ARGUMENT_VALUE",
+			WantErrCode: "M_INVALID_PARAM",
 		},
 	}
 	for _, tst := range tsts {
@@ -157,7 +157,7 @@ func TestBadLoginFromJSONReader(t *testing.T) {
 			if errRes == nil {
 				cleanup(ctx, nil)
 				t.Fatalf("LoginFromJSONReader err: got %+v, want code %q", errRes, tst.WantErrCode)
-			} else if merr, ok := errRes.JSON.(*jsonerror.MatrixError); ok && merr.ErrCode != tst.WantErrCode {
+			} else if merr, ok := errRes.JSON.(*spec.MatrixError); ok && merr.ErrCode != tst.WantErrCode {
 				t.Fatalf("LoginFromJSONReader err: got %+v, want code %q", errRes, tst.WantErrCode)
 			}
 		})
diff --git a/clientapi/auth/login_token.go b/clientapi/auth/login_token.go
index 845eb5de..073f728d 100644
--- a/clientapi/auth/login_token.go
+++ b/clientapi/auth/login_token.go
@@ -20,9 +20,9 @@ import (
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/setup/config"
 	uapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -48,13 +48,13 @@ func (t *LoginTypeToken) LoginFromJSON(ctx context.Context, reqBytes []byte) (*L
 	var res uapi.QueryLoginTokenResponse
 	if err := t.UserAPI.QueryLoginToken(ctx, &uapi.QueryLoginTokenRequest{Token: r.Token}, &res); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("UserAPI.QueryLoginToken failed")
-		jsonErr := jsonerror.InternalServerError()
+		jsonErr := spec.InternalServerError()
 		return nil, nil, &jsonErr
 	}
 	if res.Data == nil {
 		return nil, nil, &util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("invalid login token"),
+			JSON: spec.Forbidden("invalid login token"),
 		}
 	}
 
diff --git a/clientapi/auth/password.go b/clientapi/auth/password.go
index f2b0383a..fb7def02 100644
--- a/clientapi/auth/password.go
+++ b/clientapi/auth/password.go
@@ -21,10 +21,10 @@ import (
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/userutil"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -65,26 +65,26 @@ func (t *LoginTypePassword) Login(ctx context.Context, req interface{}) (*Login,
 	if username == "" {
 		return nil, &util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.BadJSON("A username must be supplied."),
+			JSON: spec.BadJSON("A username must be supplied."),
 		}
 	}
 	if len(r.Password) == 0 {
 		return nil, &util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.BadJSON("A password must be supplied."),
+			JSON: spec.BadJSON("A password must be supplied."),
 		}
 	}
 	localpart, domain, err := userutil.ParseUsernameParam(username, t.Config.Matrix)
 	if err != nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.InvalidUsername(err.Error()),
+			JSON: spec.InvalidUsername(err.Error()),
 		}
 	}
 	if !t.Config.Matrix.IsLocalServerName(domain) {
 		return nil, &util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.InvalidUsername("The server name is not known."),
+			JSON: spec.InvalidUsername("The server name is not known."),
 		}
 	}
 	// Squash username to all lowercase letters
@@ -97,7 +97,7 @@ func (t *LoginTypePassword) Login(ctx context.Context, req interface{}) (*Login,
 	if err != nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("Unable to fetch account by password."),
+			JSON: spec.Unknown("Unable to fetch account by password."),
 		}
 	}
 
@@ -112,7 +112,7 @@ func (t *LoginTypePassword) Login(ctx context.Context, req interface{}) (*Login,
 		if err != nil {
 			return nil, &util.JSONResponse{
 				Code: http.StatusInternalServerError,
-				JSON: jsonerror.Unknown("Unable to fetch account by password."),
+				JSON: spec.Unknown("Unable to fetch account by password."),
 			}
 		}
 		// Technically we could tell them if the user does not exist by checking if err == sql.ErrNoRows
@@ -120,7 +120,7 @@ func (t *LoginTypePassword) Login(ctx context.Context, req interface{}) (*Login,
 		if !res.Exists {
 			return nil, &util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden("The username or password was incorrect or the account does not exist."),
+				JSON: spec.Forbidden("The username or password was incorrect or the account does not exist."),
 			}
 		}
 	}
diff --git a/clientapi/auth/user_interactive.go b/clientapi/auth/user_interactive.go
index 9971bf8a..58d34865 100644
--- a/clientapi/auth/user_interactive.go
+++ b/clientapi/auth/user_interactive.go
@@ -20,9 +20,9 @@ import (
 	"net/http"
 	"sync"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 	"github.com/sirupsen/logrus"
 	"github.com/tidwall/gjson"
@@ -178,7 +178,7 @@ func (u *UserInteractive) NewSession() *util.JSONResponse {
 	sessionID, err := GenerateAccessToken()
 	if err != nil {
 		logrus.WithError(err).Error("failed to generate session ID")
-		res := jsonerror.InternalServerError()
+		res := spec.InternalServerError()
 		return &res
 	}
 	u.Lock()
@@ -193,14 +193,14 @@ func (u *UserInteractive) ResponseWithChallenge(sessionID string, response inter
 	mixedObjects := make(map[string]interface{})
 	b, err := json.Marshal(response)
 	if err != nil {
-		ise := jsonerror.InternalServerError()
+		ise := spec.InternalServerError()
 		return &ise
 	}
 	_ = json.Unmarshal(b, &mixedObjects)
 	challenge := u.challenge(sessionID)
 	b, err = json.Marshal(challenge.JSON)
 	if err != nil {
-		ise := jsonerror.InternalServerError()
+		ise := spec.InternalServerError()
 		return &ise
 	}
 	_ = json.Unmarshal(b, &mixedObjects)
@@ -234,7 +234,7 @@ func (u *UserInteractive) Verify(ctx context.Context, bodyBytes []byte, device *
 	if !ok {
 		return nil, &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Unknown auth.type: " + authType),
+			JSON: spec.BadJSON("Unknown auth.type: " + authType),
 		}
 	}
 
@@ -250,7 +250,7 @@ func (u *UserInteractive) Verify(ctx context.Context, bodyBytes []byte, device *
 		if !u.IsSingleStageFlow(authType) {
 			return nil, &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.Unknown("The auth.session is missing or unknown."),
+				JSON: spec.Unknown("The auth.session is missing or unknown."),
 			}
 		}
 	}
diff --git a/clientapi/httputil/httputil.go b/clientapi/httputil/httputil.go
index 74f84f1e..aea0c3db 100644
--- a/clientapi/httputil/httputil.go
+++ b/clientapi/httputil/httputil.go
@@ -20,7 +20,7 @@ import (
 	"net/http"
 	"unicode/utf8"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -32,7 +32,7 @@ func UnmarshalJSONRequest(req *http.Request, iface interface{}) *util.JSONRespon
 	body, err := io.ReadAll(req.Body)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("io.ReadAll failed")
-		resp := jsonerror.InternalServerError()
+		resp := spec.InternalServerError()
 		return &resp
 	}
 
@@ -43,7 +43,7 @@ func UnmarshalJSON(body []byte, iface interface{}) *util.JSONResponse {
 	if !utf8.Valid(body) {
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("Body contains invalid UTF-8"),
+			JSON: spec.NotJSON("Body contains invalid UTF-8"),
 		}
 	}
 
@@ -53,7 +53,7 @@ func UnmarshalJSON(body []byte, iface interface{}) *util.JSONResponse {
 		// valid JSON with incorrect types for values.
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 	return nil
diff --git a/clientapi/jsonerror/jsonerror.go b/clientapi/jsonerror/jsonerror.go
deleted file mode 100644
index 436e168a..00000000
--- a/clientapi/jsonerror/jsonerror.go
+++ /dev/null
@@ -1,246 +0,0 @@
-// Copyright 2017 Vector Creations Ltd
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package jsonerror
-
-import (
-	"context"
-	"fmt"
-	"net/http"
-
-	"github.com/matrix-org/gomatrixserverlib"
-	"github.com/matrix-org/util"
-	"github.com/sirupsen/logrus"
-)
-
-// MatrixError represents the "standard error response" in Matrix.
-// http://matrix.org/docs/spec/client_server/r0.2.0.html#api-standards
-type MatrixError struct {
-	ErrCode string `json:"errcode"`
-	Err     string `json:"error"`
-}
-
-func (e MatrixError) Error() string {
-	return fmt.Sprintf("%s: %s", e.ErrCode, e.Err)
-}
-
-// InternalServerError returns a 500 Internal Server Error in a matrix-compliant
-// format.
-func InternalServerError() util.JSONResponse {
-	return util.JSONResponse{
-		Code: http.StatusInternalServerError,
-		JSON: Unknown("Internal Server Error"),
-	}
-}
-
-// Unknown is an unexpected error
-func Unknown(msg string) *MatrixError {
-	return &MatrixError{"M_UNKNOWN", msg}
-}
-
-// Forbidden is an error when the client tries to access a resource
-// they are not allowed to access.
-func Forbidden(msg string) *MatrixError {
-	return &MatrixError{"M_FORBIDDEN", msg}
-}
-
-// BadJSON is an error when the client supplies malformed JSON.
-func BadJSON(msg string) *MatrixError {
-	return &MatrixError{"M_BAD_JSON", msg}
-}
-
-// BadAlias is an error when the client supplies a bad alias.
-func BadAlias(msg string) *MatrixError {
-	return &MatrixError{"M_BAD_ALIAS", msg}
-}
-
-// NotJSON is an error when the client supplies something that is not JSON
-// to a JSON endpoint.
-func NotJSON(msg string) *MatrixError {
-	return &MatrixError{"M_NOT_JSON", msg}
-}
-
-// NotFound is an error when the client tries to access an unknown resource.
-func NotFound(msg string) *MatrixError {
-	return &MatrixError{"M_NOT_FOUND", msg}
-}
-
-// MissingArgument is an error when the client tries to access a resource
-// without providing an argument that is required.
-func MissingArgument(msg string) *MatrixError {
-	return &MatrixError{"M_MISSING_ARGUMENT", msg}
-}
-
-// InvalidArgumentValue is an error when the client tries to provide an
-// invalid value for a valid argument
-func InvalidArgumentValue(msg string) *MatrixError {
-	return &MatrixError{"M_INVALID_ARGUMENT_VALUE", msg}
-}
-
-// MissingToken is an error when the client tries to access a resource which
-// requires authentication without supplying credentials.
-func MissingToken(msg string) *MatrixError {
-	return &MatrixError{"M_MISSING_TOKEN", msg}
-}
-
-// UnknownToken is an error when the client tries to access a resource which
-// requires authentication and supplies an unrecognised token
-func UnknownToken(msg string) *MatrixError {
-	return &MatrixError{"M_UNKNOWN_TOKEN", msg}
-}
-
-// WeakPassword is an error which is returned when the client tries to register
-// using a weak password. http://matrix.org/docs/spec/client_server/r0.2.0.html#password-based
-func WeakPassword(msg string) *MatrixError {
-	return &MatrixError{"M_WEAK_PASSWORD", msg}
-}
-
-// InvalidUsername is an error returned when the client tries to register an
-// invalid username
-func InvalidUsername(msg string) *MatrixError {
-	return &MatrixError{"M_INVALID_USERNAME", msg}
-}
-
-// UserInUse is an error returned when the client tries to register an
-// username that already exists
-func UserInUse(msg string) *MatrixError {
-	return &MatrixError{"M_USER_IN_USE", msg}
-}
-
-// RoomInUse is an error returned when the client tries to make a room
-// that already exists
-func RoomInUse(msg string) *MatrixError {
-	return &MatrixError{"M_ROOM_IN_USE", msg}
-}
-
-// ASExclusive is an error returned when an application service tries to
-// register an username that is outside of its registered namespace, or if a
-// user attempts to register a username or room alias within an exclusive
-// namespace.
-func ASExclusive(msg string) *MatrixError {
-	return &MatrixError{"M_EXCLUSIVE", msg}
-}
-
-// GuestAccessForbidden is an error which is returned when the client is
-// forbidden from accessing a resource as a guest.
-func GuestAccessForbidden(msg string) *MatrixError {
-	return &MatrixError{"M_GUEST_ACCESS_FORBIDDEN", msg}
-}
-
-// InvalidSignature is an error which is returned when the client tries
-// to upload invalid signatures.
-func InvalidSignature(msg string) *MatrixError {
-	return &MatrixError{"M_INVALID_SIGNATURE", msg}
-}
-
-// InvalidParam is an error that is returned when a parameter was invalid,
-// traditionally with cross-signing.
-func InvalidParam(msg string) *MatrixError {
-	return &MatrixError{"M_INVALID_PARAM", msg}
-}
-
-// MissingParam is an error that is returned when a parameter was incorrect,
-// traditionally with cross-signing.
-func MissingParam(msg string) *MatrixError {
-	return &MatrixError{"M_MISSING_PARAM", msg}
-}
-
-// UnableToAuthoriseJoin is an error that is returned when a server can't
-// determine whether to allow a restricted join or not.
-func UnableToAuthoriseJoin(msg string) *MatrixError {
-	return &MatrixError{"M_UNABLE_TO_AUTHORISE_JOIN", msg}
-}
-
-// LeaveServerNoticeError is an error returned when trying to reject an invite
-// for a server notice room.
-func LeaveServerNoticeError() *MatrixError {
-	return &MatrixError{
-		ErrCode: "M_CANNOT_LEAVE_SERVER_NOTICE_ROOM",
-		Err:     "You cannot reject this invite",
-	}
-}
-
-// ErrRoomKeysVersion is an error returned by `PUT /room_keys/keys`
-type ErrRoomKeysVersion struct {
-	MatrixError
-	CurrentVersion string `json:"current_version"`
-}
-
-// WrongBackupVersionError is an error returned by `PUT /room_keys/keys`
-func WrongBackupVersionError(currentVersion string) *ErrRoomKeysVersion {
-	return &ErrRoomKeysVersion{
-		MatrixError: MatrixError{
-			ErrCode: "M_WRONG_ROOM_KEYS_VERSION",
-			Err:     "Wrong backup version.",
-		},
-		CurrentVersion: currentVersion,
-	}
-}
-
-type IncompatibleRoomVersionError struct {
-	RoomVersion string `json:"room_version"`
-	Error       string `json:"error"`
-	Code        string `json:"errcode"`
-}
-
-// IncompatibleRoomVersion is an error which is returned when the client
-// requests a room with a version that is unsupported.
-func IncompatibleRoomVersion(roomVersion gomatrixserverlib.RoomVersion) *IncompatibleRoomVersionError {
-	return &IncompatibleRoomVersionError{
-		Code:        "M_INCOMPATIBLE_ROOM_VERSION",
-		RoomVersion: string(roomVersion),
-		Error:       "Your homeserver does not support the features required to join this room",
-	}
-}
-
-// UnsupportedRoomVersion is an error which is returned when the client
-// requests a room with a version that is unsupported.
-func UnsupportedRoomVersion(msg string) *MatrixError {
-	return &MatrixError{"M_UNSUPPORTED_ROOM_VERSION", msg}
-}
-
-// LimitExceededError is a rate-limiting error.
-type LimitExceededError struct {
-	MatrixError
-	RetryAfterMS int64 `json:"retry_after_ms,omitempty"`
-}
-
-// LimitExceeded is an error when the client tries to send events too quickly.
-func LimitExceeded(msg string, retryAfterMS int64) *LimitExceededError {
-	return &LimitExceededError{
-		MatrixError:  MatrixError{"M_LIMIT_EXCEEDED", msg},
-		RetryAfterMS: retryAfterMS,
-	}
-}
-
-// NotTrusted is an error which is returned when the client asks the server to
-// proxy a request (e.g. 3PID association) to a server that isn't trusted
-func NotTrusted(serverName string) *MatrixError {
-	return &MatrixError{
-		ErrCode: "M_SERVER_NOT_TRUSTED",
-		Err:     fmt.Sprintf("Untrusted server '%s'", serverName),
-	}
-}
-
-// InternalAPIError is returned when Dendrite failed to reach an internal API.
-func InternalAPIError(ctx context.Context, err error) util.JSONResponse {
-	logrus.WithContext(ctx).WithError(err).Error("Error reaching an internal API")
-	return util.JSONResponse{
-		Code: http.StatusInternalServerError,
-		JSON: &MatrixError{
-			ErrCode: "M_INTERNAL_SERVER_ERROR",
-			Err:     "Dendrite encountered an error reaching an internal API.",
-		},
-	}
-}
diff --git a/clientapi/jsonerror/jsonerror_test.go b/clientapi/jsonerror/jsonerror_test.go
deleted file mode 100644
index 9f3754cb..00000000
--- a/clientapi/jsonerror/jsonerror_test.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// Copyright 2017 Vector Creations Ltd
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package jsonerror
-
-import (
-	"encoding/json"
-	"testing"
-)
-
-func TestLimitExceeded(t *testing.T) {
-	e := LimitExceeded("too fast", 5000)
-	jsonBytes, err := json.Marshal(&e)
-	if err != nil {
-		t.Fatalf("TestLimitExceeded: Failed to marshal LimitExceeded error. %s", err.Error())
-	}
-	want := `{"errcode":"M_LIMIT_EXCEEDED","error":"too fast","retry_after_ms":5000}`
-	if string(jsonBytes) != want {
-		t.Errorf("TestLimitExceeded: want %s, got %s", want, string(jsonBytes))
-	}
-}
-
-func TestForbidden(t *testing.T) {
-	e := Forbidden("you shall not pass")
-	jsonBytes, err := json.Marshal(&e)
-	if err != nil {
-		t.Fatalf("TestForbidden: Failed to marshal Forbidden error. %s", err.Error())
-	}
-	want := `{"errcode":"M_FORBIDDEN","error":"you shall not pass"}`
-	if string(jsonBytes) != want {
-		t.Errorf("TestForbidden: want %s, got %s", want, string(jsonBytes))
-	}
-}
diff --git a/clientapi/routing/account_data.go b/clientapi/routing/account_data.go
index 4742b124..572b28ef 100644
--- a/clientapi/routing/account_data.go
+++ b/clientapi/routing/account_data.go
@@ -21,11 +21,11 @@ import (
 	"net/http"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 
 	"github.com/matrix-org/util"
 )
@@ -38,7 +38,7 @@ func GetAccountData(
 	if userID != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID does not match the current user"),
+			JSON: spec.Forbidden("userID does not match the current user"),
 		}
 	}
 
@@ -69,7 +69,7 @@ func GetAccountData(
 
 	return util.JSONResponse{
 		Code: http.StatusNotFound,
-		JSON: jsonerror.NotFound("data not found"),
+		JSON: spec.NotFound("data not found"),
 	}
 }
 
@@ -81,7 +81,7 @@ func SaveAccountData(
 	if userID != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID does not match the current user"),
+			JSON: spec.Forbidden("userID does not match the current user"),
 		}
 	}
 
@@ -90,27 +90,27 @@ func SaveAccountData(
 	if req.Body == http.NoBody {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("Content not JSON"),
+			JSON: spec.NotJSON("Content not JSON"),
 		}
 	}
 
 	if dataType == "m.fully_read" || dataType == "m.push_rules" {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(fmt.Sprintf("Unable to modify %q using this API", dataType)),
+			JSON: spec.Forbidden(fmt.Sprintf("Unable to modify %q using this API", dataType)),
 		}
 	}
 
 	body, err := io.ReadAll(req.Body)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("io.ReadAll failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if !json.Valid(body) {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Bad JSON content"),
+			JSON: spec.BadJSON("Bad JSON content"),
 		}
 	}
 
@@ -157,7 +157,7 @@ func SaveReadMarker(
 	if r.FullyRead != "" {
 		data, err := json.Marshal(fullyReadEvent{EventID: r.FullyRead})
 		if err != nil {
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		dataReq := api.InputAccountDataRequest{
diff --git a/clientapi/routing/admin.go b/clientapi/routing/admin.go
index a5fc4ec4..4d2cea68 100644
--- a/clientapi/routing/admin.go
+++ b/clientapi/routing/admin.go
@@ -17,7 +17,6 @@ import (
 	"github.com/nats-io/nats.go"
 	"github.com/sirupsen/logrus"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/httputil"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
@@ -37,7 +36,7 @@ func AdminEvacuateRoom(req *http.Request, rsAPI roomserverAPI.ClientRoomserverAP
 	case eventutil.ErrRoomNoExists:
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(err.Error()),
+			JSON: spec.NotFound(err.Error()),
 		}
 	default:
 		logrus.WithError(err).WithField("roomID", vars["roomID"]).Error("Failed to evacuate room")
@@ -91,7 +90,7 @@ func AdminResetPassword(req *http.Request, cfg *config.ClientAPI, device *api.De
 	if req.Body == nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("Missing request body"),
+			JSON: spec.Unknown("Missing request body"),
 		}
 	}
 	vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
@@ -104,7 +103,7 @@ func AdminResetPassword(req *http.Request, cfg *config.ClientAPI, device *api.De
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(err.Error()),
+			JSON: spec.InvalidParam(err.Error()),
 		}
 	}
 	accAvailableResp := &api.QueryAccountAvailabilityResponse{}
@@ -114,13 +113,13 @@ func AdminResetPassword(req *http.Request, cfg *config.ClientAPI, device *api.De
 	}, accAvailableResp); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalAPIError(req.Context(), err),
+			JSON: spec.InternalServerError(),
 		}
 	}
 	if accAvailableResp.Available {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.Unknown("User does not exist"),
+			JSON: spec.Unknown("User does not exist"),
 		}
 	}
 	request := struct {
@@ -129,13 +128,13 @@ func AdminResetPassword(req *http.Request, cfg *config.ClientAPI, device *api.De
 	if err = json.NewDecoder(req.Body).Decode(&request); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("Failed to decode request body: " + err.Error()),
+			JSON: spec.Unknown("Failed to decode request body: " + err.Error()),
 		}
 	}
 	if request.Password == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Expecting non-empty password."),
+			JSON: spec.MissingParam("Expecting non-empty password."),
 		}
 	}
 
@@ -153,7 +152,7 @@ func AdminResetPassword(req *http.Request, cfg *config.ClientAPI, device *api.De
 	if err := userAPI.PerformPasswordUpdate(req.Context(), updateReq, updateRes); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("Failed to perform password update: " + err.Error()),
+			JSON: spec.Unknown("Failed to perform password update: " + err.Error()),
 		}
 	}
 	return util.JSONResponse{
@@ -170,7 +169,7 @@ func AdminReindex(req *http.Request, cfg *config.ClientAPI, device *api.Device,
 	_, err := natsClient.RequestMsg(nats.NewMsg(cfg.Matrix.JetStream.Prefixed(jetstream.InputFulltextReindex)), time.Second*10)
 	if err != nil {
 		logrus.WithError(err).Error("failed to publish nats message")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -192,7 +191,7 @@ func AdminMarkAsStale(req *http.Request, cfg *config.ClientAPI, keyAPI api.Clien
 	if cfg.Matrix.IsLocalServerName(domain) {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidParam("Can not mark local device list as stale"),
+			JSON: spec.InvalidParam("Can not mark local device list as stale"),
 		}
 	}
 
@@ -203,7 +202,7 @@ func AdminMarkAsStale(req *http.Request, cfg *config.ClientAPI, keyAPI api.Clien
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown(fmt.Sprintf("Failed to mark device list as stale: %s", err)),
+			JSON: spec.Unknown(fmt.Sprintf("Failed to mark device list as stale: %s", err)),
 		}
 	}
 	return util.JSONResponse{
@@ -221,21 +220,21 @@ func AdminDownloadState(req *http.Request, device *api.Device, rsAPI roomserverA
 	if !ok {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Expecting room ID."),
+			JSON: spec.MissingParam("Expecting room ID."),
 		}
 	}
 	serverName, ok := vars["serverName"]
 	if !ok {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Expecting remote server name."),
+			JSON: spec.MissingParam("Expecting remote server name."),
 		}
 	}
 	if err = rsAPI.PerformAdminDownloadState(req.Context(), roomID, device.UserID, spec.ServerName(serverName)); err != nil {
 		if errors.Is(err, eventutil.ErrRoomNoExists) {
 			return util.JSONResponse{
 				Code: 200,
-				JSON: jsonerror.NotFound(eventutil.ErrRoomNoExists.Error()),
+				JSON: spec.NotFound(eventutil.ErrRoomNoExists.Error()),
 			}
 		}
 		logrus.WithError(err).WithFields(logrus.Fields{
diff --git a/clientapi/routing/admin_whois.go b/clientapi/routing/admin_whois.go
index f1cbd346..cb2b8a26 100644
--- a/clientapi/routing/admin_whois.go
+++ b/clientapi/routing/admin_whois.go
@@ -17,8 +17,8 @@ package routing
 import (
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 
 	"github.com/matrix-org/util"
 )
@@ -51,7 +51,7 @@ func GetAdminWhois(
 	if !allowed {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID does not match the current user"),
+			JSON: spec.Forbidden("userID does not match the current user"),
 		}
 	}
 
@@ -61,7 +61,7 @@ func GetAdminWhois(
 	}, &queryRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("GetAdminWhois failed to query user devices")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	devices := make(map[string]deviceInfo)
diff --git a/clientapi/routing/aliases.go b/clientapi/routing/aliases.go
index 5c2df79d..87c1f9ff 100644
--- a/clientapi/routing/aliases.go
+++ b/clientapi/routing/aliases.go
@@ -19,12 +19,10 @@ import (
 	"fmt"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/spec"
-
 	"github.com/matrix-org/util"
 )
 
@@ -64,12 +62,12 @@ func GetAliases(
 		var queryRes api.QueryMembershipForUserResponse
 		if err := rsAPI.QueryMembershipForUser(req.Context(), &queryReq, &queryRes); err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("rsAPI.QueryMembershipsForRoom failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		if !queryRes.IsInRoom {
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden("You aren't a member of this room."),
+				JSON: spec.Forbidden("You aren't a member of this room."),
 			}
 		}
 	}
diff --git a/clientapi/routing/createroom.go b/clientapi/routing/createroom.go
index abf5b4f4..f0cdd6f5 100644
--- a/clientapi/routing/createroom.go
+++ b/clientapi/routing/createroom.go
@@ -32,7 +32,6 @@ import (
 	"github.com/matrix-org/gomatrixserverlib/spec"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/gomatrixserverlib"
@@ -75,7 +74,7 @@ func (r createRoomRequest) Validate() *util.JSONResponse {
 	if strings.ContainsAny(r.RoomAliasName, whitespace+":") {
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("room_alias_name cannot contain whitespace or ':'"),
+			JSON: spec.BadJSON("room_alias_name cannot contain whitespace or ':'"),
 		}
 	}
 	for _, userID := range r.Invite {
@@ -87,7 +86,7 @@ func (r createRoomRequest) Validate() *util.JSONResponse {
 		if _, _, err := gomatrixserverlib.SplitID('@', userID); err != nil {
 			return &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON("user id must be in the form @localpart:domain"),
+				JSON: spec.BadJSON("user id must be in the form @localpart:domain"),
 			}
 		}
 	}
@@ -96,7 +95,7 @@ func (r createRoomRequest) Validate() *util.JSONResponse {
 	default:
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("preset must be any of 'private_chat', 'trusted_private_chat', 'public_chat'"),
+			JSON: spec.BadJSON("preset must be any of 'private_chat', 'trusted_private_chat', 'public_chat'"),
 		}
 	}
 
@@ -108,7 +107,7 @@ func (r createRoomRequest) Validate() *util.JSONResponse {
 	if err != nil {
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("malformed creation_content"),
+			JSON: spec.BadJSON("malformed creation_content"),
 		}
 	}
 
@@ -117,7 +116,7 @@ func (r createRoomRequest) Validate() *util.JSONResponse {
 	if err != nil {
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("malformed creation_content"),
+			JSON: spec.BadJSON("malformed creation_content"),
 		}
 	}
 
@@ -156,7 +155,7 @@ func CreateRoom(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(err.Error()),
+			JSON: spec.InvalidParam(err.Error()),
 		}
 	}
 	return createRoom(req.Context(), r, device, cfg, profileAPI, rsAPI, asAPI, evTime)
@@ -175,12 +174,12 @@ func createRoom(
 	_, userDomain, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !cfg.Matrix.IsLocalServerName(userDomain) {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(fmt.Sprintf("User domain %q not configured locally", userDomain)),
+			JSON: spec.Forbidden(fmt.Sprintf("User domain %q not configured locally", userDomain)),
 		}
 	}
 
@@ -200,7 +199,7 @@ func createRoom(
 		if roomVersionError != nil {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.UnsupportedRoomVersion(roomVersionError.Error()),
+				JSON: spec.UnsupportedRoomVersion(roomVersionError.Error()),
 			}
 		}
 		roomVersion = candidateVersion
@@ -219,7 +218,7 @@ func createRoom(
 	profile, err := appserviceAPI.RetrieveUserProfile(ctx, userID, asAPI, profileAPI)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("appserviceAPI.RetrieveUserProfile failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	createContent := map[string]interface{}{}
@@ -228,7 +227,7 @@ func createRoom(
 			util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for creation_content failed")
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON("invalid create content"),
+				JSON: spec.BadJSON("invalid create content"),
 			}
 		}
 	}
@@ -249,7 +248,7 @@ func createRoom(
 			util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for power_level_content_override failed")
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON("malformed power_level_content_override"),
+				JSON: spec.BadJSON("malformed power_level_content_override"),
 			}
 		}
 	}
@@ -343,12 +342,12 @@ func createRoom(
 		err = rsAPI.GetRoomIDForAlias(ctx, &hasAliasReq, &aliasResp)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("aliasAPI.GetRoomIDForAlias failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		if aliasResp.RoomID != "" {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.RoomInUse("Room ID already exists."),
+				JSON: spec.RoomInUse("Room ID already exists."),
 			}
 		}
 
@@ -437,7 +436,7 @@ func createRoom(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("unknown room version"),
+			JSON: spec.BadJSON("unknown room version"),
 		}
 	}
 
@@ -456,7 +455,7 @@ func createRoom(
 		err = builder.SetContent(e.Content)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("builder.SetContent failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		if i > 0 {
 			builder.PrevEvents = []gomatrixserverlib.EventReference{builtEvents[i-1].EventReference()}
@@ -464,17 +463,17 @@ func createRoom(
 		var ev gomatrixserverlib.PDU
 		if err = builder.AddAuthEvents(&authEvents); err != nil {
 			util.GetLogger(ctx).WithError(err).Error("AddAuthEvents failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		ev, err = builder.Build(evTime, userDomain, cfg.Matrix.KeyID, cfg.Matrix.PrivateKey)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("buildEvent failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		if err = gomatrixserverlib.Allowed(ev, &authEvents); err != nil {
 			util.GetLogger(ctx).WithError(err).Error("gomatrixserverlib.Allowed failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		// Add the event to the list of auth events
@@ -482,7 +481,7 @@ func createRoom(
 		err = authEvents.AddEvent(ev)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("authEvents.AddEvent failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
@@ -497,7 +496,7 @@ func createRoom(
 	}
 	if err = roomserverAPI.SendInputRoomEvents(ctx, rsAPI, device.UserDomain(), inputs, false); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("roomserverAPI.SendInputRoomEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// TODO(#269): Reserve room alias while we create the room. This stops us
@@ -514,13 +513,13 @@ func createRoom(
 		err = rsAPI.SetRoomAlias(ctx, &aliasReq, &aliasResp)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("aliasAPI.SetRoomAlias failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		if aliasResp.AliasExists {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.RoomInUse("Room alias already exists."),
+				JSON: spec.RoomInUse("Room alias already exists."),
 			}
 		}
 	}
@@ -584,12 +583,12 @@ func createRoom(
 			case roomserverAPI.ErrInvalidID:
 				return util.JSONResponse{
 					Code: http.StatusBadRequest,
-					JSON: jsonerror.Unknown(e.Error()),
+					JSON: spec.Unknown(e.Error()),
 				}
 			case roomserverAPI.ErrNotAllowed:
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden(e.Error()),
+					JSON: spec.Forbidden(e.Error()),
 				}
 			case nil:
 			default:
@@ -597,7 +596,7 @@ func createRoom(
 				sentry.CaptureException(err)
 				return util.JSONResponse{
 					Code: http.StatusInternalServerError,
-					JSON: jsonerror.InternalServerError(),
+					JSON: spec.InternalServerError(),
 				}
 			}
 		}
@@ -610,7 +609,7 @@ func createRoom(
 			Visibility: spec.Public,
 		}); err != nil {
 			util.GetLogger(ctx).WithError(err).Error("failed to publish room")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
diff --git a/clientapi/routing/deactivate.go b/clientapi/routing/deactivate.go
index 3f4f539f..78cf9fe3 100644
--- a/clientapi/routing/deactivate.go
+++ b/clientapi/routing/deactivate.go
@@ -5,9 +5,9 @@ import (
 	"net/http"
 
 	"github.com/matrix-org/dendrite/clientapi/auth"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -24,7 +24,7 @@ func Deactivate(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be read: " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be read: " + err.Error()),
 		}
 	}
 
@@ -36,7 +36,7 @@ func Deactivate(
 	localpart, serverName, err := gomatrixserverlib.SplitID('@', login.Username())
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	var res api.PerformAccountDeactivationResponse
@@ -46,7 +46,7 @@ func Deactivate(
 	}, &res)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("userAPI.PerformAccountDeactivation failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/device.go b/clientapi/routing/device.go
index 331bacc3..6209d8e9 100644
--- a/clientapi/routing/device.go
+++ b/clientapi/routing/device.go
@@ -22,9 +22,9 @@ import (
 
 	"github.com/matrix-org/dendrite/clientapi/auth"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 	"github.com/tidwall/gjson"
 )
@@ -60,7 +60,7 @@ func GetDeviceByID(
 	}, &queryRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("QueryDevices failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	var targetDevice *api.Device
 	for _, device := range queryRes.Devices {
@@ -72,7 +72,7 @@ func GetDeviceByID(
 	if targetDevice == nil {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Unknown device"),
+			JSON: spec.NotFound("Unknown device"),
 		}
 	}
 
@@ -97,7 +97,7 @@ func GetDevicesByLocalpart(
 	}, &queryRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("QueryDevices failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	res := devicesJSON{}
@@ -139,12 +139,12 @@ func UpdateDeviceByID(
 	}, &performRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("PerformDeviceUpdate failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !performRes.DeviceExists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.Forbidden("device does not exist"),
+			JSON: spec.Forbidden("device does not exist"),
 		}
 	}
 
@@ -174,7 +174,7 @@ func DeleteDeviceById(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be read: " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be read: " + err.Error()),
 		}
 	}
 
@@ -184,7 +184,7 @@ func DeleteDeviceById(
 		if dev != deviceID {
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden("session and device mismatch"),
+				JSON: spec.Forbidden("session and device mismatch"),
 			}
 		}
 	}
@@ -206,7 +206,7 @@ func DeleteDeviceById(
 	localpart, _, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// make sure that the access token being used matches the login creds used for user interactive auth, else
@@ -214,7 +214,7 @@ func DeleteDeviceById(
 	if login.Username() != localpart && login.Username() != device.UserID {
 		return util.JSONResponse{
 			Code: 403,
-			JSON: jsonerror.Forbidden("Cannot delete another user's device"),
+			JSON: spec.Forbidden("Cannot delete another user's device"),
 		}
 	}
 
@@ -224,7 +224,7 @@ func DeleteDeviceById(
 		DeviceIDs: []string{deviceID},
 	}, &res); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("userAPI.PerformDeviceDeletion failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	deleteOK = true
@@ -245,7 +245,7 @@ func DeleteDevices(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be read: " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be read: " + err.Error()),
 		}
 	}
 	defer req.Body.Close() // nolint:errcheck
@@ -259,14 +259,14 @@ func DeleteDevices(
 	if login.Username() != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("unable to delete devices for other user"),
+			JSON: spec.Forbidden("unable to delete devices for other user"),
 		}
 	}
 
 	payload := devicesDeleteJSON{}
 	if err = json.Unmarshal(bodyBytes, &payload); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("unable to unmarshal device deletion request")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	var res api.PerformDeviceDeletionResponse
@@ -275,7 +275,7 @@ func DeleteDevices(
 		DeviceIDs: payload.Devices,
 	}, &res); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("userAPI.PerformDeviceDeletion failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/directory.go b/clientapi/routing/directory.go
index 11ae5739..0ca9475d 100644
--- a/clientapi/routing/directory.go
+++ b/clientapi/routing/directory.go
@@ -24,7 +24,6 @@ import (
 	"github.com/matrix-org/util"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	federationAPI "github.com/matrix-org/dendrite/federationapi/api"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
@@ -56,7 +55,7 @@ func DirectoryRoom(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Room alias must be in the form '#localpart:domain'"),
+			JSON: spec.BadJSON("Room alias must be in the form '#localpart:domain'"),
 		}
 	}
 
@@ -70,7 +69,7 @@ func DirectoryRoom(
 	queryRes := &roomserverAPI.GetRoomIDForAliasResponse{}
 	if err = rsAPI.GetRoomIDForAlias(req.Context(), queryReq, queryRes); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("rsAPI.GetRoomIDForAlias failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	res.RoomID = queryRes.RoomID
@@ -84,7 +83,7 @@ func DirectoryRoom(
 				// TODO: Return 502 if the remote server errored.
 				// TODO: Return 504 if the remote server timed out.
 				util.GetLogger(req.Context()).WithError(fedErr).Error("federation.LookupRoomAlias failed")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 			res.RoomID = fedRes.RoomID
 			res.fillServers(fedRes.Servers)
@@ -93,7 +92,7 @@ func DirectoryRoom(
 		if res.RoomID == "" {
 			return util.JSONResponse{
 				Code: http.StatusNotFound,
-				JSON: jsonerror.NotFound(
+				JSON: spec.NotFound(
 					fmt.Sprintf("Room alias %s not found", roomAlias),
 				),
 			}
@@ -103,7 +102,7 @@ func DirectoryRoom(
 		var joinedHostsRes federationAPI.QueryJoinedHostServerNamesInRoomResponse
 		if err = fedSenderAPI.QueryJoinedHostServerNamesInRoom(req.Context(), &joinedHostsReq, &joinedHostsRes); err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("fedSenderAPI.QueryJoinedHostServerNamesInRoom failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		res.fillServers(joinedHostsRes.ServerNames)
 	}
@@ -126,14 +125,14 @@ func SetLocalAlias(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Room alias must be in the form '#localpart:domain'"),
+			JSON: spec.BadJSON("Room alias must be in the form '#localpart:domain'"),
 		}
 	}
 
 	if !cfg.Matrix.IsLocalServerName(domain) {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Alias must be on local homeserver"),
+			JSON: spec.Forbidden("Alias must be on local homeserver"),
 		}
 	}
 
@@ -146,7 +145,7 @@ func SetLocalAlias(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("User ID must be in the form '@localpart:domain'"),
+			JSON: spec.BadJSON("User ID must be in the form '@localpart:domain'"),
 		}
 	}
 	for _, appservice := range cfg.Derived.ApplicationServices {
@@ -158,7 +157,7 @@ func SetLocalAlias(
 					if namespace.Exclusive && namespace.RegexpObject.MatchString(alias) {
 						return util.JSONResponse{
 							Code: http.StatusBadRequest,
-							JSON: jsonerror.ASExclusive("Alias is reserved by an application service"),
+							JSON: spec.ASExclusive("Alias is reserved by an application service"),
 						}
 					}
 				}
@@ -181,13 +180,13 @@ func SetLocalAlias(
 	var queryRes roomserverAPI.SetRoomAliasResponse
 	if err := rsAPI.SetRoomAlias(req.Context(), &queryReq, &queryRes); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("aliasAPI.SetRoomAlias failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if queryRes.AliasExists {
 		return util.JSONResponse{
 			Code: http.StatusConflict,
-			JSON: jsonerror.Unknown("The alias " + alias + " already exists."),
+			JSON: spec.Unknown("The alias " + alias + " already exists."),
 		}
 	}
 
@@ -211,20 +210,20 @@ func RemoveLocalAlias(
 	var queryRes roomserverAPI.RemoveRoomAliasResponse
 	if err := rsAPI.RemoveRoomAlias(req.Context(), &queryReq, &queryRes); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("aliasAPI.RemoveRoomAlias failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if !queryRes.Found {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("The alias does not exist."),
+			JSON: spec.NotFound("The alias does not exist."),
 		}
 	}
 
 	if !queryRes.Removed {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You do not have permission to remove this alias."),
+			JSON: spec.Forbidden("You do not have permission to remove this alias."),
 		}
 	}
 
@@ -249,7 +248,7 @@ func GetVisibility(
 	}, &res)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("QueryPublishedRooms failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	var v roomVisibility
@@ -287,7 +286,7 @@ func SetVisibility(
 	err := rsAPI.QueryLatestEventsAndState(req.Context(), &queryEventsReq, &queryEventsRes)
 	if err != nil || len(queryEventsRes.StateEvents) == 0 {
 		util.GetLogger(req.Context()).WithError(err).Error("could not query events from room")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// NOTSPEC: Check if the user's power is greater than power required to change m.room.canonical_alias event
@@ -295,7 +294,7 @@ func SetVisibility(
 	if power.UserLevel(dev.UserID) < power.EventLevel(spec.MRoomCanonicalAlias, true) {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID doesn't have power level to change visibility"),
+			JSON: spec.Forbidden("userID doesn't have power level to change visibility"),
 		}
 	}
 
@@ -309,7 +308,7 @@ func SetVisibility(
 		Visibility: v.Visibility,
 	}); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("failed to publish room")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -325,7 +324,7 @@ func SetVisibilityAS(
 	if dev.AccountType != userapi.AccountTypeAppService {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Only appservice may use this endpoint"),
+			JSON: spec.Forbidden("Only appservice may use this endpoint"),
 		}
 	}
 	var v roomVisibility
@@ -345,7 +344,7 @@ func SetVisibilityAS(
 		AppserviceID: dev.AppserviceID,
 	}); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("failed to publish room")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/directory_public.go b/clientapi/routing/directory_public.go
index c150d908..9718ccab 100644
--- a/clientapi/routing/directory_public.go
+++ b/clientapi/routing/directory_public.go
@@ -29,7 +29,6 @@ import (
 
 	"github.com/matrix-org/dendrite/clientapi/api"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
 )
@@ -68,7 +67,7 @@ func GetPostPublicRooms(
 	if request.IncludeAllNetworks && request.NetworkID != "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidParam("include_all_networks and third_party_instance_id can not be used together"),
+			JSON: spec.InvalidParam("include_all_networks and third_party_instance_id can not be used together"),
 		}
 	}
 
@@ -82,7 +81,7 @@ func GetPostPublicRooms(
 		)
 		if err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("failed to get public rooms")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		return util.JSONResponse{
 			Code: http.StatusOK,
@@ -93,7 +92,7 @@ func GetPostPublicRooms(
 	response, err := publicRooms(req.Context(), request, rsAPI, extRoomsProvider)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Errorf("failed to work out public rooms")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -173,7 +172,7 @@ func fillPublicRoomsReq(httpReq *http.Request, request *PublicRoomReq) *util.JSO
 	if httpReq.Method != "GET" && httpReq.Method != "POST" {
 		return &util.JSONResponse{
 			Code: http.StatusMethodNotAllowed,
-			JSON: jsonerror.NotFound("Bad method"),
+			JSON: spec.NotFound("Bad method"),
 		}
 	}
 	if httpReq.Method == "GET" {
@@ -184,7 +183,7 @@ func fillPublicRoomsReq(httpReq *http.Request, request *PublicRoomReq) *util.JSO
 			util.GetLogger(httpReq.Context()).WithError(err).Error("strconv.Atoi failed")
 			return &util.JSONResponse{
 				Code: 400,
-				JSON: jsonerror.BadJSON("limit param is not a number"),
+				JSON: spec.BadJSON("limit param is not a number"),
 			}
 		}
 		request.Limit = int64(limit)
diff --git a/clientapi/routing/joined_rooms.go b/clientapi/routing/joined_rooms.go
index 4bb353ea..51a96e4d 100644
--- a/clientapi/routing/joined_rooms.go
+++ b/clientapi/routing/joined_rooms.go
@@ -19,9 +19,9 @@ import (
 
 	"github.com/matrix-org/util"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 type getJoinedRoomsResponse struct {
@@ -40,7 +40,7 @@ func GetJoinedRooms(
 	}, &res)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("QueryRoomsForUser failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if res.RoomIDs == nil {
 		res.RoomIDs = []string{}
diff --git a/clientapi/routing/joinroom.go b/clientapi/routing/joinroom.go
index 54a9aaa4..a67d5132 100644
--- a/clientapi/routing/joinroom.go
+++ b/clientapi/routing/joinroom.go
@@ -22,7 +22,6 @@ import (
 
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/userapi/api"
@@ -75,7 +74,7 @@ func JoinRoomByIDOrAlias(
 		util.GetLogger(req.Context()).Error("Unable to query user profile, no profile found.")
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("Unable to query user profile, no profile found."),
+			JSON: spec.Unknown("Unable to query user profile, no profile found."),
 		}
 	default:
 	}
@@ -99,12 +98,12 @@ func JoinRoomByIDOrAlias(
 		case roomserverAPI.ErrInvalidID:
 			response = util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.Unknown(e.Error()),
+				JSON: spec.Unknown(e.Error()),
 			}
 		case roomserverAPI.ErrNotAllowed:
-			jsonErr := jsonerror.Forbidden(e.Error())
+			jsonErr := spec.Forbidden(e.Error())
 			if device.AccountType == api.AccountTypeGuest {
-				jsonErr = jsonerror.GuestAccessForbidden(e.Error())
+				jsonErr = spec.GuestAccessForbidden(e.Error())
 			}
 			response = util.JSONResponse{
 				Code: http.StatusForbidden,
@@ -118,12 +117,12 @@ func JoinRoomByIDOrAlias(
 		default:
 			response = util.JSONResponse{
 				Code: http.StatusInternalServerError,
-				JSON: jsonerror.InternalServerError(),
+				JSON: spec.InternalServerError(),
 			}
 			if errors.Is(err, eventutil.ErrRoomNoExists) {
 				response = util.JSONResponse{
 					Code: http.StatusNotFound,
-					JSON: jsonerror.NotFound(e.Error()),
+					JSON: spec.NotFound(e.Error()),
 				}
 			}
 		}
@@ -137,7 +136,7 @@ func JoinRoomByIDOrAlias(
 	case <-timer.C:
 		return util.JSONResponse{
 			Code: http.StatusAccepted,
-			JSON: jsonerror.Unknown("The room join will continue in the background."),
+			JSON: spec.Unknown("The room join will continue in the background."),
 		}
 	case result := <-done:
 		// Stop and drain the timer
diff --git a/clientapi/routing/key_backup.go b/clientapi/routing/key_backup.go
index 56b05db1..b7b1cadd 100644
--- a/clientapi/routing/key_backup.go
+++ b/clientapi/routing/key_backup.go
@@ -20,8 +20,8 @@ import (
 	"net/http"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -64,7 +64,7 @@ func CreateKeyBackupVersion(req *http.Request, userAPI userapi.ClientUserAPI, de
 	if len(kb.AuthData) == 0 {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("missing auth_data"),
+			JSON: spec.BadJSON("missing auth_data"),
 		}
 	}
 	version, err := userAPI.PerformKeyBackup(req.Context(), &userapi.PerformKeyBackupRequest{
@@ -98,7 +98,7 @@ func KeyBackupVersion(req *http.Request, userAPI userapi.ClientUserAPI, device *
 	if !queryResp.Exists {
 		return util.JSONResponse{
 			Code: 404,
-			JSON: jsonerror.NotFound("version not found"),
+			JSON: spec.NotFound("version not found"),
 		}
 	}
 	return util.JSONResponse{
@@ -128,7 +128,7 @@ func ModifyKeyBackupVersionAuthData(req *http.Request, userAPI userapi.ClientUse
 		Algorithm: kb.Algorithm,
 	})
 	switch e := err.(type) {
-	case *jsonerror.ErrRoomKeysVersion:
+	case *spec.ErrRoomKeysVersion:
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
 			JSON: e,
@@ -141,7 +141,7 @@ func ModifyKeyBackupVersionAuthData(req *http.Request, userAPI userapi.ClientUse
 	if !performKeyBackupResp.Exists {
 		return util.JSONResponse{
 			Code: 404,
-			JSON: jsonerror.NotFound("backup version not found"),
+			JSON: spec.NotFound("backup version not found"),
 		}
 	}
 	return util.JSONResponse{
@@ -162,7 +162,7 @@ func DeleteKeyBackupVersion(req *http.Request, userAPI userapi.ClientUserAPI, de
 	if !exists {
 		return util.JSONResponse{
 			Code: 404,
-			JSON: jsonerror.NotFound("backup version not found"),
+			JSON: spec.NotFound("backup version not found"),
 		}
 	}
 	return util.JSONResponse{
@@ -182,7 +182,7 @@ func UploadBackupKeys(
 	})
 
 	switch e := err.(type) {
-	case *jsonerror.ErrRoomKeysVersion:
+	case *spec.ErrRoomKeysVersion:
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
 			JSON: e,
@@ -194,7 +194,7 @@ func UploadBackupKeys(
 	if !performKeyBackupResp.Exists {
 		return util.JSONResponse{
 			Code: 404,
-			JSON: jsonerror.NotFound("backup version not found"),
+			JSON: spec.NotFound("backup version not found"),
 		}
 	}
 	return util.JSONResponse{
@@ -223,7 +223,7 @@ func GetBackupKeys(
 	if !queryResp.Exists {
 		return util.JSONResponse{
 			Code: 404,
-			JSON: jsonerror.NotFound("version not found"),
+			JSON: spec.NotFound("version not found"),
 		}
 	}
 	if sessionID != "" {
@@ -274,6 +274,6 @@ func GetBackupKeys(
 	}
 	return util.JSONResponse{
 		Code: 404,
-		JSON: jsonerror.NotFound("keys not found"),
+		JSON: spec.NotFound("keys not found"),
 	}
 }
diff --git a/clientapi/routing/key_crosssigning.go b/clientapi/routing/key_crosssigning.go
index 267ba1dc..6bf7c58e 100644
--- a/clientapi/routing/key_crosssigning.go
+++ b/clientapi/routing/key_crosssigning.go
@@ -20,9 +20,9 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/auth"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -71,31 +71,29 @@ func UploadCrossSigningDeviceKeys(
 	sessions.addCompletedSessionStage(sessionID, authtypes.LoginTypePassword)
 
 	uploadReq.UserID = device.UserID
-	if err := keyserverAPI.PerformUploadDeviceKeys(req.Context(), &uploadReq.PerformUploadDeviceKeysRequest, uploadRes); err != nil {
-		return jsonerror.InternalAPIError(req.Context(), err)
-	}
+	keyserverAPI.PerformUploadDeviceKeys(req.Context(), &uploadReq.PerformUploadDeviceKeysRequest, uploadRes)
 
 	if err := uploadRes.Error; err != nil {
 		switch {
 		case err.IsInvalidSignature:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidSignature(err.Error()),
+				JSON: spec.InvalidSignature(err.Error()),
 			}
 		case err.IsMissingParam:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.MissingParam(err.Error()),
+				JSON: spec.MissingParam(err.Error()),
 			}
 		case err.IsInvalidParam:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidParam(err.Error()),
+				JSON: spec.InvalidParam(err.Error()),
 			}
 		default:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.Unknown(err.Error()),
+				JSON: spec.Unknown(err.Error()),
 			}
 		}
 	}
@@ -115,31 +113,29 @@ func UploadCrossSigningDeviceSignatures(req *http.Request, keyserverAPI api.Clie
 	}
 
 	uploadReq.UserID = device.UserID
-	if err := keyserverAPI.PerformUploadDeviceSignatures(req.Context(), uploadReq, uploadRes); err != nil {
-		return jsonerror.InternalAPIError(req.Context(), err)
-	}
+	keyserverAPI.PerformUploadDeviceSignatures(req.Context(), uploadReq, uploadRes)
 
 	if err := uploadRes.Error; err != nil {
 		switch {
 		case err.IsInvalidSignature:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidSignature(err.Error()),
+				JSON: spec.InvalidSignature(err.Error()),
 			}
 		case err.IsMissingParam:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.MissingParam(err.Error()),
+				JSON: spec.MissingParam(err.Error()),
 			}
 		case err.IsInvalidParam:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidParam(err.Error()),
+				JSON: spec.InvalidParam(err.Error()),
 			}
 		default:
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.Unknown(err.Error()),
+				JSON: spec.Unknown(err.Error()),
 			}
 		}
 	}
diff --git a/clientapi/routing/keys.go b/clientapi/routing/keys.go
index 3d60fcc3..363ae3dc 100644
--- a/clientapi/routing/keys.go
+++ b/clientapi/routing/keys.go
@@ -22,8 +22,8 @@ import (
 	"github.com/matrix-org/util"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 type uploadKeysRequest struct {
@@ -67,7 +67,7 @@ func UploadKeys(req *http.Request, keyAPI api.ClientKeyAPI, device *api.Device)
 	}
 	if uploadRes.Error != nil {
 		util.GetLogger(req.Context()).WithError(uploadRes.Error).Error("Failed to PerformUploadKeys")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if len(uploadRes.KeyErrors) > 0 {
 		util.GetLogger(req.Context()).WithField("key_errors", uploadRes.KeyErrors).Error("Failed to upload one or more keys")
@@ -112,14 +112,12 @@ func QueryKeys(req *http.Request, keyAPI api.ClientKeyAPI, device *api.Device) u
 		return *resErr
 	}
 	queryRes := api.QueryKeysResponse{}
-	if err := keyAPI.QueryKeys(req.Context(), &api.QueryKeysRequest{
+	keyAPI.QueryKeys(req.Context(), &api.QueryKeysRequest{
 		UserID:        device.UserID,
 		UserToDevices: r.DeviceKeys,
 		Timeout:       r.GetTimeout(),
 		// TODO: Token?
-	}, &queryRes); err != nil {
-		return util.ErrorResponse(err)
-	}
+	}, &queryRes)
 	return util.JSONResponse{
 		Code: 200,
 		JSON: map[string]interface{}{
@@ -152,15 +150,13 @@ func ClaimKeys(req *http.Request, keyAPI api.ClientKeyAPI) util.JSONResponse {
 		return *resErr
 	}
 	claimRes := api.PerformClaimKeysResponse{}
-	if err := keyAPI.PerformClaimKeys(req.Context(), &api.PerformClaimKeysRequest{
+	keyAPI.PerformClaimKeys(req.Context(), &api.PerformClaimKeysRequest{
 		OneTimeKeys: r.OneTimeKeys,
 		Timeout:     r.GetTimeout(),
-	}, &claimRes); err != nil {
-		return jsonerror.InternalAPIError(req.Context(), err)
-	}
+	}, &claimRes)
 	if claimRes.Error != nil {
 		util.GetLogger(req.Context()).WithError(claimRes.Error).Error("failed to PerformClaimKeys")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	return util.JSONResponse{
 		Code: 200,
diff --git a/clientapi/routing/leaveroom.go b/clientapi/routing/leaveroom.go
index a7166185..fbf14826 100644
--- a/clientapi/routing/leaveroom.go
+++ b/clientapi/routing/leaveroom.go
@@ -17,9 +17,9 @@ package routing
 import (
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -41,12 +41,12 @@ func LeaveRoomByID(
 		if leaveRes.Code != 0 {
 			return util.JSONResponse{
 				Code: leaveRes.Code,
-				JSON: jsonerror.LeaveServerNoticeError(),
+				JSON: spec.LeaveServerNoticeError(),
 			}
 		}
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(err.Error()),
+			JSON: spec.Unknown(err.Error()),
 		}
 	}
 
diff --git a/clientapi/routing/login.go b/clientapi/routing/login.go
index 778c8c0c..d326bff7 100644
--- a/clientapi/routing/login.go
+++ b/clientapi/routing/login.go
@@ -19,10 +19,10 @@ import (
 	"net/http"
 
 	"github.com/matrix-org/dendrite/clientapi/auth"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/userutil"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -72,7 +72,7 @@ func Login(
 	}
 	return util.JSONResponse{
 		Code: http.StatusMethodNotAllowed,
-		JSON: jsonerror.NotFound("Bad method"),
+		JSON: spec.NotFound("Bad method"),
 	}
 }
 
@@ -83,13 +83,13 @@ func completeAuth(
 	token, err := auth.GenerateAccessToken()
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("auth.GenerateAccessToken failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	localpart, serverName, err := userutil.ParseUsernameParam(login.Username(), cfg)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("auth.ParseUsernameParam failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	var performRes userapi.PerformDeviceCreationResponse
@@ -105,7 +105,7 @@ func completeAuth(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("failed to create device: " + err.Error()),
+			JSON: spec.Unknown("failed to create device: " + err.Error()),
 		}
 	}
 
diff --git a/clientapi/routing/logout.go b/clientapi/routing/logout.go
index 73bae7af..049c88d5 100644
--- a/clientapi/routing/logout.go
+++ b/clientapi/routing/logout.go
@@ -17,8 +17,8 @@ package routing
 import (
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -33,7 +33,7 @@ func Logout(
 	}, &performRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("PerformDeviceDeletion failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -53,7 +53,7 @@ func LogoutAll(
 	}, &performRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("PerformDeviceDeletion failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/membership.go b/clientapi/routing/membership.go
index d696f2b1..9b95ba5d 100644
--- a/clientapi/routing/membership.go
+++ b/clientapi/routing/membership.go
@@ -27,7 +27,6 @@ import (
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/threepid"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/roomserver/api"
@@ -52,7 +51,7 @@ func SendBan(
 	if body.UserID == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("missing user_id"),
+			JSON: spec.BadJSON("missing user_id"),
 		}
 	}
 
@@ -69,7 +68,7 @@ func SendBan(
 	if !allowedToBan {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You don't have permission to ban this user, power level too low."),
+			JSON: spec.Forbidden("You don't have permission to ban this user, power level too low."),
 		}
 	}
 
@@ -86,7 +85,7 @@ func sendMembership(ctx context.Context, profileAPI userapi.ClientUserAPI, devic
 	)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("buildMembershipEvent failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	serverName := device.UserDomain()
@@ -101,7 +100,7 @@ func sendMembership(ctx context.Context, profileAPI userapi.ClientUserAPI, devic
 		false,
 	); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -122,7 +121,7 @@ func SendKick(
 	if body.UserID == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("missing user_id"),
+			JSON: spec.BadJSON("missing user_id"),
 		}
 	}
 
@@ -139,7 +138,7 @@ func SendKick(
 	if !allowedToKick {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You don't have permission to kick this user, power level too low."),
+			JSON: spec.Forbidden("You don't have permission to kick this user, power level too low."),
 		}
 	}
 
@@ -155,7 +154,7 @@ func SendKick(
 	if queryRes.Membership != spec.Join && queryRes.Membership != spec.Invite {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Unknown("cannot /kick banned or left users"),
+			JSON: spec.Unknown("cannot /kick banned or left users"),
 		}
 	}
 	// TODO: should we be using SendLeave instead?
@@ -174,7 +173,7 @@ func SendUnban(
 	if body.UserID == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("missing user_id"),
+			JSON: spec.BadJSON("missing user_id"),
 		}
 	}
 
@@ -196,7 +195,7 @@ func SendUnban(
 	if queryRes.Membership != spec.Ban {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("can only /unban users that are banned"),
+			JSON: spec.Unknown("can only /unban users that are banned"),
 		}
 	}
 	// TODO: should we be using SendLeave instead?
@@ -233,7 +232,7 @@ func SendInvite(
 	if body.UserID == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("missing user_id"),
+			JSON: spec.BadJSON("missing user_id"),
 		}
 	}
 
@@ -263,7 +262,7 @@ func sendInvite(
 	)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("buildMembershipEvent failed")
-		return jsonerror.InternalServerError(), err
+		return spec.InternalServerError(), err
 	}
 
 	err = rsAPI.PerformInvite(ctx, &api.PerformInviteRequest{
@@ -277,12 +276,12 @@ func sendInvite(
 	case roomserverAPI.ErrInvalidID:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(e.Error()),
+			JSON: spec.Unknown(e.Error()),
 		}, e
 	case roomserverAPI.ErrNotAllowed:
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(e.Error()),
+			JSON: spec.Forbidden(e.Error()),
 		}, e
 	case nil:
 	default:
@@ -290,7 +289,7 @@ func sendInvite(
 		sentry.CaptureException(err)
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}, err
 	}
 
@@ -377,7 +376,7 @@ func extractRequestData(req *http.Request) (body *threepid.MembershipRequest, ev
 	if err != nil {
 		resErr = &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(err.Error()),
+			JSON: spec.InvalidParam(err.Error()),
 		}
 		return
 	}
@@ -402,27 +401,27 @@ func checkAndProcessThreepid(
 	if err == threepid.ErrMissingParameter {
 		return inviteStored, &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	} else if err == threepid.ErrNotTrusted {
 		return inviteStored, &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotTrusted(body.IDServer),
+			JSON: spec.NotTrusted(body.IDServer),
 		}
 	} else if err == eventutil.ErrRoomNoExists {
 		return inviteStored, &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(err.Error()),
+			JSON: spec.NotFound(err.Error()),
 		}
 	} else if e, ok := err.(gomatrixserverlib.BadJSONError); ok {
 		return inviteStored, &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(e.Error()),
+			JSON: spec.BadJSON(e.Error()),
 		}
 	}
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("threepid.CheckAndProcessInvite failed")
-		er := jsonerror.InternalServerError()
+		er := spec.InternalServerError()
 		return inviteStored, &er
 	}
 	return
@@ -436,13 +435,13 @@ func checkMemberInRoom(ctx context.Context, rsAPI roomserverAPI.ClientRoomserver
 	}, &membershipRes)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("QueryMembershipForUser: could not query membership for user")
-		e := jsonerror.InternalServerError()
+		e := spec.InternalServerError()
 		return &e
 	}
 	if !membershipRes.IsInRoom {
 		return &util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("user does not belong to room"),
+			JSON: spec.Forbidden("user does not belong to room"),
 		}
 	}
 	return nil
@@ -462,18 +461,18 @@ func SendForget(
 	err := rsAPI.QueryMembershipForUser(ctx, &membershipReq, &membershipRes)
 	if err != nil {
 		logger.WithError(err).Error("QueryMembershipForUser: could not query membership for user")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !membershipRes.RoomExists {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("room does not exist"),
+			JSON: spec.Forbidden("room does not exist"),
 		}
 	}
 	if membershipRes.IsInRoom {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(fmt.Sprintf("User %s is in room %s", device.UserID, roomID)),
+			JSON: spec.Unknown(fmt.Sprintf("User %s is in room %s", device.UserID, roomID)),
 		}
 	}
 
@@ -484,7 +483,7 @@ func SendForget(
 	response := roomserverAPI.PerformForgetResponse{}
 	if err := rsAPI.PerformForget(ctx, &request, &response); err != nil {
 		logger.WithError(err).Error("PerformForget: unable to forget room")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -500,14 +499,14 @@ func getPowerlevels(req *http.Request, rsAPI roomserverAPI.ClientRoomserverAPI,
 	if plEvent == nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You don't have permission to perform this action, no power_levels event in this room."),
+			JSON: spec.Forbidden("You don't have permission to perform this action, no power_levels event in this room."),
 		}
 	}
 	pl, err := plEvent.PowerLevels()
 	if err != nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You don't have permission to perform this action, the power_levels event for this room is malformed so auth checks cannot be performed."),
+			JSON: spec.Forbidden("You don't have permission to perform this action, the power_levels event for this room is malformed so auth checks cannot be performed."),
 		}
 	}
 	return pl, nil
diff --git a/clientapi/routing/notification.go b/clientapi/routing/notification.go
index f593e27d..8ac12ce5 100644
--- a/clientapi/routing/notification.go
+++ b/clientapi/routing/notification.go
@@ -18,9 +18,9 @@ import (
 	"net/http"
 	"strconv"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -35,7 +35,7 @@ func GetNotifications(
 		limit, err = strconv.ParseInt(limitStr, 10, 64)
 		if err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("ParseInt(limit) failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
@@ -43,7 +43,7 @@ func GetNotifications(
 	localpart, domain, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	err = userAPI.QueryNotifications(req.Context(), &userapi.QueryNotificationsRequest{
 		Localpart:  localpart,
@@ -54,7 +54,7 @@ func GetNotifications(
 	}, &queryRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("QueryNotifications failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	util.GetLogger(req.Context()).WithField("from", req.URL.Query().Get("from")).WithField("limit", limit).WithField("only", req.URL.Query().Get("only")).WithField("next", queryRes.NextToken).Infof("QueryNotifications: len %d", len(queryRes.Notifications))
 	return util.JSONResponse{
diff --git a/clientapi/routing/openid.go b/clientapi/routing/openid.go
index 8e9be788..1ead00eb 100644
--- a/clientapi/routing/openid.go
+++ b/clientapi/routing/openid.go
@@ -17,9 +17,9 @@ package routing
 import (
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -43,7 +43,7 @@ func CreateOpenIDToken(
 	if userID != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Cannot request tokens for other users"),
+			JSON: spec.Forbidden("Cannot request tokens for other users"),
 		}
 	}
 
@@ -55,7 +55,7 @@ func CreateOpenIDToken(
 	err := userAPI.PerformOpenIDTokenCreation(req.Context(), &request, &response)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("userAPI.CreateOpenIDToken failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/password.go b/clientapi/routing/password.go
index f7f9da62..68466a77 100644
--- a/clientapi/routing/password.go
+++ b/clientapi/routing/password.go
@@ -6,11 +6,11 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/auth"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 	"github.com/sirupsen/logrus"
 )
@@ -90,7 +90,7 @@ func Password(
 	localpart, domain, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// Ask the user API to perform the password change.
@@ -102,11 +102,11 @@ func Password(
 	passwordRes := &api.PerformPasswordUpdateResponse{}
 	if err := userAPI.PerformPasswordUpdate(req.Context(), passwordReq, passwordRes); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("PerformPasswordUpdate failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !passwordRes.PasswordUpdated {
 		util.GetLogger(req.Context()).Error("Expected password to have been updated but wasn't")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// If the request asks us to log out all other devices then
@@ -120,7 +120,7 @@ func Password(
 		logoutRes := &api.PerformDeviceDeletionResponse{}
 		if err := userAPI.PerformDeviceDeletion(req.Context(), logoutReq, logoutRes); err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("PerformDeviceDeletion failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		pushersReq := &api.PerformPusherDeletionRequest{
@@ -130,7 +130,7 @@ func Password(
 		}
 		if err := userAPI.PerformPusherDeletion(req.Context(), pushersReq, &struct{}{}); err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("PerformPusherDeletion failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
diff --git a/clientapi/routing/peekroom.go b/clientapi/routing/peekroom.go
index 3937b9ad..af486f6d 100644
--- a/clientapi/routing/peekroom.go
+++ b/clientapi/routing/peekroom.go
@@ -18,7 +18,6 @@ import (
 	"encoding/json"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrix"
@@ -61,12 +60,12 @@ func PeekRoomByIDOrAlias(
 	case roomserverAPI.ErrInvalidID:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(e.Error()),
+			JSON: spec.Unknown(e.Error()),
 		}
 	case roomserverAPI.ErrNotAllowed:
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(e.Error()),
+			JSON: spec.Forbidden(e.Error()),
 		}
 	case *gomatrix.HTTPError:
 		return util.JSONResponse{
@@ -76,7 +75,7 @@ func PeekRoomByIDOrAlias(
 	case nil:
 	default:
 		logrus.WithError(err).WithField("roomID", roomIDOrAlias).Errorf("Failed to peek room")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// if this user is already joined to the room, we let them peek anyway
@@ -107,12 +106,12 @@ func UnpeekRoomByID(
 	case roomserverAPI.ErrInvalidID:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(e.Error()),
+			JSON: spec.Unknown(e.Error()),
 		}
 	case nil:
 	default:
 		logrus.WithError(err).WithField("roomID", roomID).Errorf("Failed to un-peek room")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/presence.go b/clientapi/routing/presence.go
index c50b0943..d915f060 100644
--- a/clientapi/routing/presence.go
+++ b/clientapi/routing/presence.go
@@ -21,7 +21,6 @@ import (
 	"time"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/setup/jetstream"
@@ -54,7 +53,7 @@ func SetPresence(
 	if device.UserID != userID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Unable to set presence for other user."),
+			JSON: spec.Forbidden("Unable to set presence for other user."),
 		}
 	}
 	var presence presenceReq
@@ -67,7 +66,7 @@ func SetPresence(
 	if !ok {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(fmt.Sprintf("Unknown presence '%s'.", presence.Presence)),
+			JSON: spec.Unknown(fmt.Sprintf("Unknown presence '%s'.", presence.Presence)),
 		}
 	}
 	err := producer.SendPresence(req.Context(), userID, presenceStatus, presence.StatusMsg)
@@ -75,7 +74,7 @@ func SetPresence(
 		log.WithError(err).Errorf("failed to update presence")
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
@@ -100,7 +99,7 @@ func GetPresence(
 		log.WithError(err).Errorf("unable to get presence")
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
@@ -119,7 +118,7 @@ func GetPresence(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
diff --git a/clientapi/routing/profile.go b/clientapi/routing/profile.go
index 765ad7cb..8e88e7c8 100644
--- a/clientapi/routing/profile.go
+++ b/clientapi/routing/profile.go
@@ -26,13 +26,11 @@ import (
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
-
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/util"
 )
@@ -49,12 +47,12 @@ func GetProfile(
 		if err == appserviceAPI.ErrProfileNotExists {
 			return util.JSONResponse{
 				Code: http.StatusNotFound,
-				JSON: jsonerror.NotFound("The user does not exist or does not have a profile"),
+				JSON: spec.NotFound("The user does not exist or does not have a profile"),
 			}
 		}
 
 		util.GetLogger(req.Context()).WithError(err).Error("getProfile failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -95,7 +93,7 @@ func SetAvatarURL(
 	if userID != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID does not match the current user"),
+			JSON: spec.Forbidden("userID does not match the current user"),
 		}
 	}
 
@@ -106,20 +104,20 @@ func SetAvatarURL(
 	if r.AvatarURL == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("'avatar_url' must be supplied."),
+			JSON: spec.BadJSON("'avatar_url' must be supplied."),
 		}
 	}
 
 	localpart, domain, err := gomatrixserverlib.SplitID('@', userID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if !cfg.Matrix.IsLocalServerName(domain) {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID does not belong to a locally configured domain"),
+			JSON: spec.Forbidden("userID does not belong to a locally configured domain"),
 		}
 	}
 
@@ -127,14 +125,14 @@ func SetAvatarURL(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(err.Error()),
+			JSON: spec.InvalidParam(err.Error()),
 		}
 	}
 
 	profile, changed, err := profileAPI.SetAvatarURL(req.Context(), localpart, domain, r.AvatarURL)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("profileAPI.SetAvatarURL failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	// No need to build new membership events, since nothing changed
 	if !changed {
@@ -184,7 +182,7 @@ func SetDisplayName(
 	if userID != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID does not match the current user"),
+			JSON: spec.Forbidden("userID does not match the current user"),
 		}
 	}
 
@@ -195,20 +193,20 @@ func SetDisplayName(
 	if r.DisplayName == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("'displayname' must be supplied."),
+			JSON: spec.BadJSON("'displayname' must be supplied."),
 		}
 	}
 
 	localpart, domain, err := gomatrixserverlib.SplitID('@', userID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if !cfg.Matrix.IsLocalServerName(domain) {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("userID does not belong to a locally configured domain"),
+			JSON: spec.Forbidden("userID does not belong to a locally configured domain"),
 		}
 	}
 
@@ -216,14 +214,14 @@ func SetDisplayName(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(err.Error()),
+			JSON: spec.InvalidParam(err.Error()),
 		}
 	}
 
 	profile, changed, err := profileAPI.SetDisplayName(req.Context(), localpart, domain, r.DisplayName)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("profileAPI.SetDisplayName failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	// No need to build new membership events, since nothing changed
 	if !changed {
@@ -256,13 +254,13 @@ func updateProfile(
 	}, &res)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("QueryRoomsForUser failed")
-		return jsonerror.InternalServerError(), err
+		return spec.InternalServerError(), err
 	}
 
 	_, domain, err := gomatrixserverlib.SplitID('@', userID)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError(), err
+		return spec.InternalServerError(), err
 	}
 
 	events, err := buildMembershipEvents(
@@ -273,16 +271,16 @@ func updateProfile(
 	case gomatrixserverlib.BadJSONError:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(e.Error()),
+			JSON: spec.BadJSON(e.Error()),
 		}, e
 	default:
 		util.GetLogger(ctx).WithError(err).Error("buildMembershipEvents failed")
-		return jsonerror.InternalServerError(), e
+		return spec.InternalServerError(), e
 	}
 
 	if err := api.SendEvents(ctx, rsAPI, api.KindNew, events, device.UserDomain(), domain, domain, nil, true); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError(), err
+		return spec.InternalServerError(), err
 	}
 	return util.JSONResponse{}, nil
 }
diff --git a/clientapi/routing/pusher.go b/clientapi/routing/pusher.go
index 89ec824b..2f51583f 100644
--- a/clientapi/routing/pusher.go
+++ b/clientapi/routing/pusher.go
@@ -19,9 +19,9 @@ import (
 	"net/url"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -34,7 +34,7 @@ func GetPushers(
 	localpart, domain, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	err = userAPI.QueryPushers(req.Context(), &userapi.QueryPushersRequest{
 		Localpart:  localpart,
@@ -42,7 +42,7 @@ func GetPushers(
 	}, &queryRes)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("QueryPushers failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	for i := range queryRes.Pushers {
 		queryRes.Pushers[i].SessionID = 0
@@ -63,7 +63,7 @@ func SetPusher(
 	localpart, domain, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	body := userapi.PerformPusherSetRequest{}
 	if resErr := httputil.UnmarshalJSONRequest(req, &body); resErr != nil {
@@ -99,7 +99,7 @@ func SetPusher(
 	err = userAPI.PerformPusherSet(req.Context(), &body, &struct{}{})
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("PerformPusherSet failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -111,6 +111,6 @@ func SetPusher(
 func invalidParam(msg string) util.JSONResponse {
 	return util.JSONResponse{
 		Code: http.StatusBadRequest,
-		JSON: jsonerror.InvalidParam(msg),
+		JSON: spec.InvalidParam(msg),
 	}
 }
diff --git a/clientapi/routing/pushrules.go b/clientapi/routing/pushrules.go
index f1a539ad..7be6d2a7 100644
--- a/clientapi/routing/pushrules.go
+++ b/clientapi/routing/pushrules.go
@@ -7,17 +7,17 @@ import (
 	"net/http"
 	"reflect"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/pushrules"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
 func errorResponse(ctx context.Context, err error, msg string, args ...interface{}) util.JSONResponse {
-	if eerr, ok := err.(*jsonerror.MatrixError); ok {
+	if eerr, ok := err.(*spec.MatrixError); ok {
 		var status int
 		switch eerr.ErrCode {
-		case "M_INVALID_ARGUMENT_VALUE":
+		case "M_INVALID_PARAM":
 			status = http.StatusBadRequest
 		case "M_NOT_FOUND":
 			status = http.StatusNotFound
@@ -27,7 +27,7 @@ func errorResponse(ctx context.Context, err error, msg string, args ...interface
 		return util.MatrixErrorResponse(status, eerr.ErrCode, eerr.Err)
 	}
 	util.GetLogger(ctx).WithError(err).Errorf(msg, args...)
-	return jsonerror.InternalServerError()
+	return spec.InternalServerError()
 }
 
 func GetAllPushRules(ctx context.Context, device *userapi.Device, userAPI userapi.ClientUserAPI) util.JSONResponse {
@@ -48,7 +48,7 @@ func GetPushRulesByScope(ctx context.Context, scope string, device *userapi.Devi
 	}
 	ruleSet := pushRuleSetByScope(ruleSets, pushrules.Scope(scope))
 	if ruleSet == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rule set"), "pushRuleSetByScope failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rule set"), "pushRuleSetByScope failed")
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -63,12 +63,12 @@ func GetPushRulesByKind(ctx context.Context, scope, kind string, device *userapi
 	}
 	ruleSet := pushRuleSetByScope(ruleSets, pushrules.Scope(scope))
 	if ruleSet == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rule set"), "pushRuleSetByScope failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rule set"), "pushRuleSetByScope failed")
 	}
 	rulesPtr := pushRuleSetKindPointer(ruleSet, pushrules.Kind(kind))
 	// Even if rulesPtr is not nil, there may not be any rules for this kind
 	if rulesPtr == nil || (rulesPtr != nil && len(*rulesPtr) == 0) {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rules kind"), "pushRuleSetKindPointer failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rules kind"), "pushRuleSetKindPointer failed")
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -83,15 +83,15 @@ func GetPushRuleByRuleID(ctx context.Context, scope, kind, ruleID string, device
 	}
 	ruleSet := pushRuleSetByScope(ruleSets, pushrules.Scope(scope))
 	if ruleSet == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rule set"), "pushRuleSetByScope failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rule set"), "pushRuleSetByScope failed")
 	}
 	rulesPtr := pushRuleSetKindPointer(ruleSet, pushrules.Kind(kind))
 	if rulesPtr == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rules kind"), "pushRuleSetKindPointer failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rules kind"), "pushRuleSetKindPointer failed")
 	}
 	i := pushRuleIndexByID(*rulesPtr, ruleID)
 	if i < 0 {
-		return errorResponse(ctx, jsonerror.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
+		return errorResponse(ctx, spec.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -104,14 +104,14 @@ func PutPushRuleByRuleID(ctx context.Context, scope, kind, ruleID, afterRuleID,
 	if err := json.NewDecoder(body).Decode(&newRule); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	}
 	newRule.RuleID = ruleID
 
 	errs := pushrules.ValidateRule(pushrules.Kind(kind), &newRule)
 	if len(errs) > 0 {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue(errs[0].Error()), "rule sanity check failed: %v", errs)
+		return errorResponse(ctx, spec.InvalidParam(errs[0].Error()), "rule sanity check failed: %v", errs)
 	}
 
 	ruleSets, err := userAPI.QueryPushRules(ctx, device.UserID)
@@ -120,12 +120,12 @@ func PutPushRuleByRuleID(ctx context.Context, scope, kind, ruleID, afterRuleID,
 	}
 	ruleSet := pushRuleSetByScope(ruleSets, pushrules.Scope(scope))
 	if ruleSet == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rule set"), "pushRuleSetByScope failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rule set"), "pushRuleSetByScope failed")
 	}
 	rulesPtr := pushRuleSetKindPointer(ruleSet, pushrules.Kind(kind))
 	if rulesPtr == nil {
 		// while this should be impossible (ValidateRule would already return an error), better keep it around
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rules kind"), "pushRuleSetKindPointer failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rules kind"), "pushRuleSetKindPointer failed")
 	}
 	i := pushRuleIndexByID(*rulesPtr, ruleID)
 	if i >= 0 && afterRuleID == "" && beforeRuleID == "" {
@@ -172,15 +172,15 @@ func DeletePushRuleByRuleID(ctx context.Context, scope, kind, ruleID string, dev
 	}
 	ruleSet := pushRuleSetByScope(ruleSets, pushrules.Scope(scope))
 	if ruleSet == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rule set"), "pushRuleSetByScope failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rule set"), "pushRuleSetByScope failed")
 	}
 	rulesPtr := pushRuleSetKindPointer(ruleSet, pushrules.Kind(kind))
 	if rulesPtr == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rules kind"), "pushRuleSetKindPointer failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rules kind"), "pushRuleSetKindPointer failed")
 	}
 	i := pushRuleIndexByID(*rulesPtr, ruleID)
 	if i < 0 {
-		return errorResponse(ctx, jsonerror.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
+		return errorResponse(ctx, spec.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
 	}
 
 	*rulesPtr = append((*rulesPtr)[:i], (*rulesPtr)[i+1:]...)
@@ -203,15 +203,15 @@ func GetPushRuleAttrByRuleID(ctx context.Context, scope, kind, ruleID, attr stri
 	}
 	ruleSet := pushRuleSetByScope(ruleSets, pushrules.Scope(scope))
 	if ruleSet == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rule set"), "pushRuleSetByScope failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rule set"), "pushRuleSetByScope failed")
 	}
 	rulesPtr := pushRuleSetKindPointer(ruleSet, pushrules.Kind(kind))
 	if rulesPtr == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rules kind"), "pushRuleSetKindPointer failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rules kind"), "pushRuleSetKindPointer failed")
 	}
 	i := pushRuleIndexByID(*rulesPtr, ruleID)
 	if i < 0 {
-		return errorResponse(ctx, jsonerror.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
+		return errorResponse(ctx, spec.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -226,7 +226,7 @@ func PutPushRuleAttrByRuleID(ctx context.Context, scope, kind, ruleID, attr stri
 	if err := json.NewDecoder(body).Decode(&newPartialRule); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	}
 	if newPartialRule.Actions == nil {
@@ -249,15 +249,15 @@ func PutPushRuleAttrByRuleID(ctx context.Context, scope, kind, ruleID, attr stri
 	}
 	ruleSet := pushRuleSetByScope(ruleSets, pushrules.Scope(scope))
 	if ruleSet == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rule set"), "pushRuleSetByScope failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rule set"), "pushRuleSetByScope failed")
 	}
 	rulesPtr := pushRuleSetKindPointer(ruleSet, pushrules.Kind(kind))
 	if rulesPtr == nil {
-		return errorResponse(ctx, jsonerror.InvalidArgumentValue("invalid push rules kind"), "pushRuleSetKindPointer failed")
+		return errorResponse(ctx, spec.InvalidParam("invalid push rules kind"), "pushRuleSetKindPointer failed")
 	}
 	i := pushRuleIndexByID(*rulesPtr, ruleID)
 	if i < 0 {
-		return errorResponse(ctx, jsonerror.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
+		return errorResponse(ctx, spec.NotFound("push rule ID not found"), "pushRuleIndexByID failed")
 	}
 
 	if !reflect.DeepEqual(attrGet((*rulesPtr)[i]), attrGet(&newPartialRule)) {
@@ -313,7 +313,7 @@ func pushRuleAttrGetter(attr string) (func(*pushrules.Rule) interface{}, error)
 	case "enabled":
 		return func(rule *pushrules.Rule) interface{} { return rule.Enabled }, nil
 	default:
-		return nil, jsonerror.InvalidArgumentValue("invalid push rule attribute")
+		return nil, spec.InvalidParam("invalid push rule attribute")
 	}
 }
 
@@ -324,7 +324,7 @@ func pushRuleAttrSetter(attr string) (func(dest, src *pushrules.Rule), error) {
 	case "enabled":
 		return func(dest, src *pushrules.Rule) { dest.Enabled = src.Enabled }, nil
 	default:
-		return nil, jsonerror.InvalidArgumentValue("invalid push rule attribute")
+		return nil, spec.InvalidParam("invalid push rule attribute")
 	}
 }
 
@@ -338,10 +338,10 @@ func findPushRuleInsertionIndex(rules []*pushrules.Rule, afterID, beforeID strin
 			}
 		}
 		if i == len(rules) {
-			return 0, jsonerror.NotFound("after: rule ID not found")
+			return 0, spec.NotFound("after: rule ID not found")
 		}
 		if rules[i].Default {
-			return 0, jsonerror.NotFound("after: rule ID must not be a default rule")
+			return 0, spec.NotFound("after: rule ID must not be a default rule")
 		}
 		// We stopped on the "after" match to differentiate
 		// not-found from is-last-entry. Now we move to the earliest
@@ -356,10 +356,10 @@ func findPushRuleInsertionIndex(rules []*pushrules.Rule, afterID, beforeID strin
 			}
 		}
 		if i == len(rules) {
-			return 0, jsonerror.NotFound("before: rule ID not found")
+			return 0, spec.NotFound("before: rule ID not found")
 		}
 		if rules[i].Default {
-			return 0, jsonerror.NotFound("before: rule ID must not be a default rule")
+			return 0, spec.NotFound("before: rule ID must not be a default rule")
 		}
 	}
 
diff --git a/clientapi/routing/receipt.go b/clientapi/routing/receipt.go
index 634b60b7..0bbb20b9 100644
--- a/clientapi/routing/receipt.go
+++ b/clientapi/routing/receipt.go
@@ -20,7 +20,6 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/gomatrixserverlib/spec"
 
@@ -49,7 +48,7 @@ func SetReceipt(req *http.Request, userAPI api.ClientUserAPI, syncProducer *prod
 	case "m.fully_read":
 		data, err := json.Marshal(fullyReadEvent{EventID: eventID})
 		if err != nil {
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		dataReq := api.InputAccountDataRequest{
diff --git a/clientapi/routing/redaction.go b/clientapi/routing/redaction.go
index a65cf673..12391d26 100644
--- a/clientapi/routing/redaction.go
+++ b/clientapi/routing/redaction.go
@@ -24,7 +24,6 @@ import (
 	"github.com/matrix-org/util"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/internal/transactions"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
@@ -63,13 +62,13 @@ func SendRedaction(
 	if ev == nil {
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.NotFound("unknown event ID"), // TODO: is it ok to leak existence?
+			JSON: spec.NotFound("unknown event ID"), // TODO: is it ok to leak existence?
 		}
 	}
 	if ev.RoomID() != roomID {
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.NotFound("cannot redact event in another room"),
+			JSON: spec.NotFound("cannot redact event in another room"),
 		}
 	}
 
@@ -85,14 +84,14 @@ func SendRedaction(
 		if plEvent == nil {
 			return util.JSONResponse{
 				Code: 403,
-				JSON: jsonerror.Forbidden("You don't have permission to redact this event, no power_levels event in this room."),
+				JSON: spec.Forbidden("You don't have permission to redact this event, no power_levels event in this room."),
 			}
 		}
 		pl, err := plEvent.PowerLevels()
 		if err != nil {
 			return util.JSONResponse{
 				Code: 403,
-				JSON: jsonerror.Forbidden(
+				JSON: spec.Forbidden(
 					"You don't have permission to redact this event, the power_levels event for this room is malformed so auth checks cannot be performed.",
 				),
 			}
@@ -102,7 +101,7 @@ func SendRedaction(
 	if !allowedToRedact {
 		return util.JSONResponse{
 			Code: 403,
-			JSON: jsonerror.Forbidden("You don't have permission to redact this event, power level too low."),
+			JSON: spec.Forbidden("You don't have permission to redact this event, power level too low."),
 		}
 	}
 
@@ -122,12 +121,12 @@ func SendRedaction(
 	err := proto.SetContent(r)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("proto.SetContent failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	identity, err := cfg.Matrix.SigningIdentityFor(device.UserDomain())
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	var queryRes roomserverAPI.QueryLatestEventsAndStateResponse
@@ -135,13 +134,13 @@ func SendRedaction(
 	if err == eventutil.ErrRoomNoExists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Room does not exist"),
+			JSON: spec.NotFound("Room does not exist"),
 		}
 	}
 	domain := device.UserDomain()
 	if err = roomserverAPI.SendEvents(context.Background(), rsAPI, roomserverAPI.KindNew, []*types.HeaderedEvent{e}, device.UserDomain(), domain, domain, nil, false); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Errorf("failed to SendEvents")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	res := util.JSONResponse{
diff --git a/clientapi/routing/register.go b/clientapi/routing/register.go
index 35dd4846..615ff201 100644
--- a/clientapi/routing/register.go
+++ b/clientapi/routing/register.go
@@ -46,7 +46,6 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/auth"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/userutil"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 )
@@ -428,7 +427,7 @@ func validateApplicationService(
 	if matchedApplicationService == nil {
 		return "", &util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.UnknownToken("Supplied access_token does not match any known application service"),
+			JSON: spec.UnknownToken("Supplied access_token does not match any known application service"),
 		}
 	}
 
@@ -439,7 +438,7 @@ func validateApplicationService(
 		// If we didn't find any matches, return M_EXCLUSIVE
 		return "", &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.ASExclusive(fmt.Sprintf(
+			JSON: spec.ASExclusive(fmt.Sprintf(
 				"Supplied username %s did not match any namespaces for application service ID: %s", username, matchedApplicationService.ID)),
 		}
 	}
@@ -448,7 +447,7 @@ func validateApplicationService(
 	if UsernameMatchesMultipleExclusiveNamespaces(cfg, userID) {
 		return "", &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.ASExclusive(fmt.Sprintf(
+			JSON: spec.ASExclusive(fmt.Sprintf(
 				"Supplied username %s matches multiple exclusive application service namespaces. Only 1 match allowed", username)),
 		}
 	}
@@ -474,7 +473,7 @@ func Register(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("Unable to read request body"),
+			JSON: spec.NotJSON("Unable to read request body"),
 		}
 	}
 
@@ -518,7 +517,7 @@ func Register(
 	if _, err = strconv.ParseInt(r.Username, 10, 64); err == nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidUsername("Numeric user IDs are reserved"),
+			JSON: spec.InvalidUsername("Numeric user IDs are reserved"),
 		}
 	}
 	// Auto generate a numeric username if r.Username is empty
@@ -529,7 +528,7 @@ func Register(
 		nres := &userapi.QueryNumericLocalpartResponse{}
 		if err = userAPI.QueryNumericLocalpart(req.Context(), nreq, nres); err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("userAPI.QueryNumericLocalpart failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		r.Username = strconv.FormatInt(nres.ID, 10)
 	}
@@ -552,7 +551,7 @@ func Register(
 		// type is not known or specified)
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("A known registration type (e.g. m.login.application_service) must be specified if an access_token is provided"),
+			JSON: spec.MissingParam("A known registration type (e.g. m.login.application_service) must be specified if an access_token is provided"),
 		}
 	default:
 		// Spec-compliant case (neither the access_token nor the login type are
@@ -590,7 +589,7 @@ func handleGuestRegistration(
 	if !registrationEnabled || !guestsEnabled {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(
+			JSON: spec.Forbidden(
 				fmt.Sprintf("Guest registration is disabled on %q", r.ServerName),
 			),
 		}
@@ -604,7 +603,7 @@ func handleGuestRegistration(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("failed to create account: " + err.Error()),
+			JSON: spec.Unknown("failed to create account: " + err.Error()),
 		}
 	}
 	token, err := tokens.GenerateLoginToken(tokens.TokenOptions{
@@ -616,7 +615,7 @@ func handleGuestRegistration(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("Failed to generate access token"),
+			JSON: spec.Unknown("Failed to generate access token"),
 		}
 	}
 	//we don't allow guests to specify their own device_id
@@ -632,7 +631,7 @@ func handleGuestRegistration(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("failed to create device: " + err.Error()),
+			JSON: spec.Unknown("failed to create device: " + err.Error()),
 		}
 	}
 	return util.JSONResponse{
@@ -682,7 +681,7 @@ func handleRegistrationFlow(
 	if !registrationEnabled && r.Auth.Type != authtypes.LoginTypeSharedSecret {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(
+			JSON: spec.Forbidden(
 				fmt.Sprintf("Registration is disabled on %q", r.ServerName),
 			),
 		}
@@ -696,7 +695,7 @@ func handleRegistrationFlow(
 		UsernameMatchesExclusiveNamespaces(cfg, r.Username) {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.ASExclusive("This username is reserved by an application service."),
+			JSON: spec.ASExclusive("This username is reserved by an application service."),
 		}
 	}
 
@@ -706,15 +705,15 @@ func handleRegistrationFlow(
 		err := validateRecaptcha(cfg, r.Auth.Response, req.RemoteAddr)
 		switch err {
 		case ErrCaptchaDisabled:
-			return util.JSONResponse{Code: http.StatusForbidden, JSON: jsonerror.Unknown(err.Error())}
+			return util.JSONResponse{Code: http.StatusForbidden, JSON: spec.Unknown(err.Error())}
 		case ErrMissingResponse:
-			return util.JSONResponse{Code: http.StatusBadRequest, JSON: jsonerror.BadJSON(err.Error())}
+			return util.JSONResponse{Code: http.StatusBadRequest, JSON: spec.BadJSON(err.Error())}
 		case ErrInvalidCaptcha:
-			return util.JSONResponse{Code: http.StatusUnauthorized, JSON: jsonerror.BadJSON(err.Error())}
+			return util.JSONResponse{Code: http.StatusUnauthorized, JSON: spec.BadJSON(err.Error())}
 		case nil:
 		default:
 			util.GetLogger(req.Context()).WithError(err).Error("failed to validate recaptcha")
-			return util.JSONResponse{Code: http.StatusInternalServerError, JSON: jsonerror.InternalServerError()}
+			return util.JSONResponse{Code: http.StatusInternalServerError, JSON: spec.InternalServerError()}
 		}
 
 		// Add Recaptcha to the list of completed registration stages
@@ -732,7 +731,7 @@ func handleRegistrationFlow(
 	default:
 		return util.JSONResponse{
 			Code: http.StatusNotImplemented,
-			JSON: jsonerror.Unknown("unknown/unimplemented auth type"),
+			JSON: spec.Unknown("unknown/unimplemented auth type"),
 		}
 	}
 
@@ -764,7 +763,7 @@ func handleApplicationServiceRegistration(
 	if tokenErr != nil {
 		return util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.MissingToken(tokenErr.Error()),
+			JSON: spec.MissingToken(tokenErr.Error()),
 		}
 	}
 
@@ -834,14 +833,14 @@ func completeRegistration(
 	if username == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Missing username"),
+			JSON: spec.MissingParam("Missing username"),
 		}
 	}
 	// Blank passwords are only allowed by registered application services
 	if password == "" && appserviceID == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Missing password"),
+			JSON: spec.MissingParam("Missing password"),
 		}
 	}
 	var accRes userapi.PerformAccountCreationResponse
@@ -857,12 +856,12 @@ func completeRegistration(
 		if _, ok := err.(*userapi.ErrorConflict); ok { // user already exists
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.UserInUse("Desired user ID is already taken."),
+				JSON: spec.UserInUse("Desired user ID is already taken."),
 			}
 		}
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("failed to create account: " + err.Error()),
+			JSON: spec.Unknown("failed to create account: " + err.Error()),
 		}
 	}
 
@@ -884,7 +883,7 @@ func completeRegistration(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("Failed to generate access token"),
+			JSON: spec.Unknown("Failed to generate access token"),
 		}
 	}
 
@@ -893,7 +892,7 @@ func completeRegistration(
 		if err != nil {
 			return util.JSONResponse{
 				Code: http.StatusInternalServerError,
-				JSON: jsonerror.Unknown("failed to set display name: " + err.Error()),
+				JSON: spec.Unknown("failed to set display name: " + err.Error()),
 			}
 		}
 	}
@@ -911,7 +910,7 @@ func completeRegistration(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("failed to create device: " + err.Error()),
+			JSON: spec.Unknown("failed to create device: " + err.Error()),
 		}
 	}
 
@@ -1006,7 +1005,7 @@ func RegisterAvailable(
 		if v.ServerName == domain && !v.AllowRegistration {
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden(
+				JSON: spec.Forbidden(
 					fmt.Sprintf("Registration is not allowed on %q", string(v.ServerName)),
 				),
 			}
@@ -1023,7 +1022,7 @@ func RegisterAvailable(
 		if appservice.OwnsNamespaceCoveringUserId(userID) {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.UserInUse("Desired user ID is reserved by an application service."),
+				JSON: spec.UserInUse("Desired user ID is reserved by an application service."),
 			}
 		}
 	}
@@ -1036,14 +1035,14 @@ func RegisterAvailable(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.Unknown("failed to check availability:" + err.Error()),
+			JSON: spec.Unknown("failed to check availability:" + err.Error()),
 		}
 	}
 
 	if !res.Available {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UserInUse("Desired User ID is already taken."),
+			JSON: spec.UserInUse("Desired User ID is already taken."),
 		}
 	}
 
@@ -1060,7 +1059,7 @@ func handleSharedSecretRegistration(cfg *config.ClientAPI, userAPI userapi.Clien
 	if err != nil {
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.BadJSON(fmt.Sprintf("malformed json: %s", err)),
+			JSON: spec.BadJSON(fmt.Sprintf("malformed json: %s", err)),
 		}
 	}
 	valid, err := sr.IsValidMacLogin(ssrr.Nonce, ssrr.User, ssrr.Password, ssrr.Admin, ssrr.MacBytes)
@@ -1070,7 +1069,7 @@ func handleSharedSecretRegistration(cfg *config.ClientAPI, userAPI userapi.Clien
 	if !valid {
 		return util.JSONResponse{
 			Code: 403,
-			JSON: jsonerror.Forbidden("bad mac"),
+			JSON: spec.Forbidden("bad mac"),
 		}
 	}
 	// downcase capitals
diff --git a/clientapi/routing/register_test.go b/clientapi/routing/register_test.go
index b07f636d..9a60f531 100644
--- a/clientapi/routing/register_test.go
+++ b/clientapi/routing/register_test.go
@@ -28,7 +28,6 @@ import (
 	"time"
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
@@ -39,6 +38,7 @@ import (
 	"github.com/matrix-org/dendrite/test/testrig"
 	"github.com/matrix-org/dendrite/userapi"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 	"github.com/patrickmn/go-cache"
 	"github.com/stretchr/testify/assert"
@@ -306,7 +306,7 @@ func Test_register(t *testing.T) {
 			guestsDisabled: true,
 			wantResponse: util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden(`Guest registration is disabled on "test"`),
+				JSON: spec.Forbidden(`Guest registration is disabled on "test"`),
 			},
 		},
 		{
@@ -318,7 +318,7 @@ func Test_register(t *testing.T) {
 			loginType: "im.not.known",
 			wantResponse: util.JSONResponse{
 				Code: http.StatusNotImplemented,
-				JSON: jsonerror.Unknown("unknown/unimplemented auth type"),
+				JSON: spec.Unknown("unknown/unimplemented auth type"),
 			},
 		},
 		{
@@ -326,7 +326,7 @@ func Test_register(t *testing.T) {
 			registrationDisabled: true,
 			wantResponse: util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden(`Registration is disabled on "test"`),
+				JSON: spec.Forbidden(`Registration is disabled on "test"`),
 			},
 		},
 		{
@@ -344,7 +344,7 @@ func Test_register(t *testing.T) {
 			username: "success",
 			wantResponse: util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.UserInUse("Desired user ID is already taken."),
+				JSON: spec.UserInUse("Desired user ID is already taken."),
 			},
 		},
 		{
@@ -361,7 +361,7 @@ func Test_register(t *testing.T) {
 			username: "1337",
 			wantResponse: util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidUsername("Numeric user IDs are reserved"),
+				JSON: spec.InvalidUsername("Numeric user IDs are reserved"),
 			},
 		},
 		{
@@ -369,7 +369,7 @@ func Test_register(t *testing.T) {
 			loginType: authtypes.LoginTypeRecaptcha,
 			wantResponse: util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Unknown(ErrCaptchaDisabled.Error()),
+				JSON: spec.Unknown(ErrCaptchaDisabled.Error()),
 			},
 		},
 		{
@@ -378,7 +378,7 @@ func Test_register(t *testing.T) {
 			loginType:       authtypes.LoginTypeRecaptcha,
 			wantResponse: util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON(ErrMissingResponse.Error()),
+				JSON: spec.BadJSON(ErrMissingResponse.Error()),
 			},
 		},
 		{
@@ -388,7 +388,7 @@ func Test_register(t *testing.T) {
 			captchaBody:     `notvalid`,
 			wantResponse: util.JSONResponse{
 				Code: http.StatusUnauthorized,
-				JSON: jsonerror.BadJSON(ErrInvalidCaptcha.Error()),
+				JSON: spec.BadJSON(ErrInvalidCaptcha.Error()),
 			},
 		},
 		{
@@ -402,7 +402,7 @@ func Test_register(t *testing.T) {
 			enableRecaptcha: true,
 			loginType:       authtypes.LoginTypeRecaptcha,
 			captchaBody:     `i should fail for other reasons`,
-			wantResponse:    util.JSONResponse{Code: http.StatusInternalServerError, JSON: jsonerror.InternalServerError()},
+			wantResponse:    util.JSONResponse{Code: http.StatusInternalServerError, JSON: spec.InternalServerError()},
 		},
 	}
 
@@ -484,7 +484,7 @@ func Test_register(t *testing.T) {
 					if !reflect.DeepEqual(r.Flows, cfg.Derived.Registration.Flows) {
 						t.Fatalf("unexpected registration flows: %+v, want %+v", r.Flows, cfg.Derived.Registration.Flows)
 					}
-				case *jsonerror.MatrixError:
+				case *spec.MatrixError:
 					if !reflect.DeepEqual(tc.wantResponse, resp) {
 						t.Fatalf("(%s), unexpected response: %+v, want: %+v", tc.name, resp, tc.wantResponse)
 					}
@@ -541,7 +541,7 @@ func Test_register(t *testing.T) {
 				resp = Register(req, userAPI, &cfg.ClientAPI)
 
 				switch resp.JSON.(type) {
-				case *jsonerror.MatrixError:
+				case *spec.MatrixError:
 					if !reflect.DeepEqual(tc.wantResponse, resp) {
 						t.Fatalf("unexpected response: %+v, want: %+v", resp, tc.wantResponse)
 					}
diff --git a/clientapi/routing/room_tagging.go b/clientapi/routing/room_tagging.go
index 92b9e665..8802d22a 100644
--- a/clientapi/routing/room_tagging.go
+++ b/clientapi/routing/room_tagging.go
@@ -19,10 +19,10 @@ import (
 	"net/http"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrix"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -39,14 +39,14 @@ func GetTags(
 	if device.UserID != userID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Cannot retrieve another user's tags"),
+			JSON: spec.Forbidden("Cannot retrieve another user's tags"),
 		}
 	}
 
 	tagContent, err := obtainSavedTags(req, userID, roomID, userAPI)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("obtainSavedTags failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -71,7 +71,7 @@ func PutTag(
 	if device.UserID != userID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Cannot modify another user's tags"),
+			JSON: spec.Forbidden("Cannot modify another user's tags"),
 		}
 	}
 
@@ -83,7 +83,7 @@ func PutTag(
 	tagContent, err := obtainSavedTags(req, userID, roomID, userAPI)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("obtainSavedTags failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if tagContent.Tags == nil {
@@ -93,7 +93,7 @@ func PutTag(
 
 	if err = saveTagData(req, userID, roomID, userAPI, tagContent); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("saveTagData failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -118,14 +118,14 @@ func DeleteTag(
 	if device.UserID != userID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Cannot modify another user's tags"),
+			JSON: spec.Forbidden("Cannot modify another user's tags"),
 		}
 	}
 
 	tagContent, err := obtainSavedTags(req, userID, roomID, userAPI)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("obtainSavedTags failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// Check whether the tag to be deleted exists
@@ -141,7 +141,7 @@ func DeleteTag(
 
 	if err = saveTagData(req, userID, roomID, userAPI, tagContent); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("saveTagData failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/routing.go b/clientapi/routing/routing.go
index 70299e14..2a2fa665 100644
--- a/clientapi/routing/routing.go
+++ b/clientapi/routing/routing.go
@@ -33,7 +33,6 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/api"
 	"github.com/matrix-org/dendrite/clientapi/auth"
 	clientutil "github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	federationAPI "github.com/matrix-org/dendrite/federationapi/api"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -148,7 +147,7 @@ func Setup(
 				}
 				return util.JSONResponse{
 					Code: http.StatusMethodNotAllowed,
-					JSON: jsonerror.NotFound("unknown method"),
+					JSON: spec.NotFound("unknown method"),
 				}
 			}),
 		).Methods(http.MethodGet, http.MethodPost, http.MethodOptions)
@@ -659,7 +658,7 @@ func Setup(
 		httputil.MakeAuthAPI("push_rules", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue("missing trailing slash"),
+				JSON: spec.InvalidParam("missing trailing slash"),
 			}
 		}),
 	).Methods(http.MethodGet, http.MethodOptions)
@@ -674,7 +673,7 @@ func Setup(
 		httputil.MakeAuthAPI("push_rules", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue("scope, kind and rule ID must be specified"),
+				JSON: spec.InvalidParam("scope, kind and rule ID must be specified"),
 			}
 		}),
 	).Methods(http.MethodPut)
@@ -693,7 +692,7 @@ func Setup(
 		httputil.MakeAuthAPI("push_rules", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue("missing trailing slash after scope"),
+				JSON: spec.InvalidParam("missing trailing slash after scope"),
 			}
 		}),
 	).Methods(http.MethodGet, http.MethodOptions)
@@ -702,7 +701,7 @@ func Setup(
 		httputil.MakeAuthAPI("push_rules", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue("kind and rule ID must be specified"),
+				JSON: spec.InvalidParam("kind and rule ID must be specified"),
 			}
 		}),
 	).Methods(http.MethodPut)
@@ -721,7 +720,7 @@ func Setup(
 		httputil.MakeAuthAPI("push_rules", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue("missing trailing slash after kind"),
+				JSON: spec.InvalidParam("missing trailing slash after kind"),
 			}
 		}),
 	).Methods(http.MethodGet, http.MethodOptions)
@@ -730,7 +729,7 @@ func Setup(
 		httputil.MakeAuthAPI("push_rules", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue("rule ID must be specified"),
+				JSON: spec.InvalidParam("rule ID must be specified"),
 			}
 		}),
 	).Methods(http.MethodPut)
@@ -939,7 +938,7 @@ func Setup(
 			// TODO: Allow people to peek into rooms.
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.GuestAccessForbidden("Guest access not implemented"),
+				JSON: spec.GuestAccessForbidden("Guest access not implemented"),
 			}
 		}),
 	).Methods(http.MethodGet, http.MethodOptions)
@@ -1244,7 +1243,7 @@ func Setup(
 		if version == "" {
 			return util.JSONResponse{
 				Code: 400,
-				JSON: jsonerror.InvalidArgumentValue("version must be specified"),
+				JSON: spec.InvalidParam("version must be specified"),
 			}
 		}
 		var reqBody keyBackupSessionRequest
@@ -1265,7 +1264,7 @@ func Setup(
 		if version == "" {
 			return util.JSONResponse{
 				Code: 400,
-				JSON: jsonerror.InvalidArgumentValue("version must be specified"),
+				JSON: spec.InvalidParam("version must be specified"),
 			}
 		}
 		roomID := vars["roomID"]
@@ -1297,7 +1296,7 @@ func Setup(
 		if version == "" {
 			return util.JSONResponse{
 				Code: 400,
-				JSON: jsonerror.InvalidArgumentValue("version must be specified"),
+				JSON: spec.InvalidParam("version must be specified"),
 			}
 		}
 		var reqBody userapi.KeyBackupSession
diff --git a/clientapi/routing/sendevent.go b/clientapi/routing/sendevent.go
index 7e5918f2..2e3cd411 100644
--- a/clientapi/routing/sendevent.go
+++ b/clientapi/routing/sendevent.go
@@ -30,7 +30,6 @@ import (
 	"github.com/sirupsen/logrus"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/internal/transactions"
 	"github.com/matrix-org/dendrite/roomserver/api"
@@ -81,7 +80,7 @@ func SendEvent(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UnsupportedRoomVersion(err.Error()),
+			JSON: spec.UnsupportedRoomVersion(err.Error()),
 		}
 	}
 
@@ -126,7 +125,7 @@ func SendEvent(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(err.Error()),
+			JSON: spec.InvalidParam(err.Error()),
 		}
 	}
 
@@ -145,12 +144,12 @@ func SendEvent(
 		if !aliasReq.Valid() {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidParam("Request contains invalid aliases."),
+				JSON: spec.InvalidParam("Request contains invalid aliases."),
 			}
 		}
 		aliasRes := &api.GetAliasesForRoomIDResponse{}
 		if err = rsAPI.GetAliasesForRoomID(req.Context(), &api.GetAliasesForRoomIDRequest{RoomID: roomID}, aliasRes); err != nil {
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		var found int
 		requestAliases := append(aliasReq.AltAliases, aliasReq.Alias)
@@ -165,7 +164,7 @@ func SendEvent(
 		if aliasReq.Alias != "" && found < len(requestAliases) {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadAlias("No matching alias found."),
+				JSON: spec.BadAlias("No matching alias found."),
 			}
 		}
 	}
@@ -194,7 +193,7 @@ func SendEvent(
 		false,
 	); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	timeToSubmitEvent := time.Since(startedSubmittingEvent)
 	util.GetLogger(req.Context()).WithFields(logrus.Fields{
@@ -273,13 +272,13 @@ func generateSendEvent(
 	err := proto.SetContent(r)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("proto.SetContent failed")
-		resErr := jsonerror.InternalServerError()
+		resErr := spec.InternalServerError()
 		return nil, &resErr
 	}
 
 	identity, err := cfg.Matrix.SigningIdentityFor(device.UserDomain())
 	if err != nil {
-		resErr := jsonerror.InternalServerError()
+		resErr := spec.InternalServerError()
 		return nil, &resErr
 	}
 
@@ -288,27 +287,27 @@ func generateSendEvent(
 	if err == eventutil.ErrRoomNoExists {
 		return nil, &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Room does not exist"),
+			JSON: spec.NotFound("Room does not exist"),
 		}
 	} else if e, ok := err.(gomatrixserverlib.BadJSONError); ok {
 		return nil, &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(e.Error()),
+			JSON: spec.BadJSON(e.Error()),
 		}
 	} else if e, ok := err.(gomatrixserverlib.EventValidationError); ok {
 		if e.Code == gomatrixserverlib.EventValidationTooLarge {
 			return nil, &util.JSONResponse{
 				Code: http.StatusRequestEntityTooLarge,
-				JSON: jsonerror.BadJSON(e.Error()),
+				JSON: spec.BadJSON(e.Error()),
 			}
 		}
 		return nil, &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(e.Error()),
+			JSON: spec.BadJSON(e.Error()),
 		}
 	} else if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("eventutil.BuildEvent failed")
-		resErr := jsonerror.InternalServerError()
+		resErr := spec.InternalServerError()
 		return nil, &resErr
 	}
 
@@ -321,7 +320,7 @@ func generateSendEvent(
 	if err = gomatrixserverlib.Allowed(e.PDU, &provider); err != nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(err.Error()), // TODO: Is this error string comprehensible to the client?
+			JSON: spec.Forbidden(err.Error()), // TODO: Is this error string comprehensible to the client?
 		}
 	}
 
@@ -332,13 +331,13 @@ func generateSendEvent(
 			util.GetLogger(ctx).WithError(err).Error("Cannot unmarshal the event content.")
 			return nil, &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON("Cannot unmarshal the event content."),
+				JSON: spec.BadJSON("Cannot unmarshal the event content."),
 			}
 		}
 		if content["replacement_room"] == e.RoomID() {
 			return nil, &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidParam("Cannot send tombstone event that points to the same room."),
+				JSON: spec.InvalidParam("Cannot send tombstone event that points to the same room."),
 			}
 		}
 	}
diff --git a/clientapi/routing/sendtodevice.go b/clientapi/routing/sendtodevice.go
index 0c022793..6d4af072 100644
--- a/clientapi/routing/sendtodevice.go
+++ b/clientapi/routing/sendtodevice.go
@@ -19,10 +19,10 @@ import (
 	"github.com/matrix-org/util"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	"github.com/matrix-org/dendrite/internal/transactions"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 // SendToDevice handles PUT /_matrix/client/r0/sendToDevice/{eventType}/{txnId}
@@ -53,7 +53,7 @@ func SendToDevice(
 				req.Context(), device.UserID, userID, deviceID, eventType, message,
 			); err != nil {
 				util.GetLogger(req.Context()).WithError(err).Error("eduProducer.SendToDevice failed")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 		}
 	}
diff --git a/clientapi/routing/sendtyping.go b/clientapi/routing/sendtyping.go
index 9dc884d6..17532a2d 100644
--- a/clientapi/routing/sendtyping.go
+++ b/clientapi/routing/sendtyping.go
@@ -18,10 +18,10 @@ import (
 	"github.com/matrix-org/util"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/producers"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 type typingContentJSON struct {
@@ -39,7 +39,7 @@ func SendTyping(
 	if device.UserID != userID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Cannot set another user's typing state"),
+			JSON: spec.Forbidden("Cannot set another user's typing state"),
 		}
 	}
 
@@ -58,7 +58,7 @@ func SendTyping(
 
 	if err := syncProducer.SendTyping(req.Context(), userID, roomID, r.Typing, r.Timeout); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("eduProducer.Send failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/server_notices.go b/clientapi/routing/server_notices.go
index a9967adf..a418677e 100644
--- a/clientapi/routing/server_notices.go
+++ b/clientapi/routing/server_notices.go
@@ -32,12 +32,12 @@ import (
 
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/internal/transactions"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 // Unspecced server notice request
@@ -68,7 +68,7 @@ func SendServerNotice(
 	if device.AccountType != userapi.AccountTypeAdmin {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("This API can only be used by admin users."),
+			JSON: spec.Forbidden("This API can only be used by admin users."),
 		}
 	}
 
@@ -90,7 +90,7 @@ func SendServerNotice(
 	if !r.valid() {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Invalid request"),
+			JSON: spec.BadJSON("Invalid request"),
 		}
 	}
 
@@ -175,7 +175,7 @@ func SendServerNotice(
 			}}
 			if err = saveTagData(req, r.UserID, roomID, userAPI, serverAlertTag); err != nil {
 				util.GetLogger(ctx).WithError(err).Error("saveTagData failed")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 
 		default:
@@ -189,7 +189,7 @@ func SendServerNotice(
 		err := rsAPI.QueryMembershipForUser(ctx, &api.QueryMembershipForUserRequest{UserID: r.UserID, RoomID: roomID}, &membershipRes)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("unable to query membership for user")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		if !membershipRes.IsInRoom {
 			// re-invite the user
@@ -237,7 +237,7 @@ func SendServerNotice(
 		false,
 	); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	util.GetLogger(ctx).WithFields(logrus.Fields{
 		"event_id":     e.EventID(),
diff --git a/clientapi/routing/state.go b/clientapi/routing/state.go
index 705782e8..75abbda9 100644
--- a/clientapi/routing/state.go
+++ b/clientapi/routing/state.go
@@ -20,7 +20,6 @@ import (
 	"fmt"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/syncapi/synctypes"
@@ -57,12 +56,12 @@ func OnIncomingStateRequest(ctx context.Context, device *userapi.Device, rsAPI a
 		StateToFetch: []gomatrixserverlib.StateKeyTuple{},
 	}, &stateRes); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("queryAPI.QueryLatestEventsAndState failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !stateRes.RoomExists {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("room does not exist"),
+			JSON: spec.Forbidden("room does not exist"),
 		}
 	}
 
@@ -74,7 +73,7 @@ func OnIncomingStateRequest(ctx context.Context, device *userapi.Device, rsAPI a
 			content := map[string]string{}
 			if err := json.Unmarshal(ev.Content(), &content); err != nil {
 				util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for history visibility failed")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 			if visibility, ok := content["history_visibility"]; ok {
 				worldReadable = visibility == "world_readable"
@@ -100,14 +99,14 @@ func OnIncomingStateRequest(ctx context.Context, device *userapi.Device, rsAPI a
 		}, &membershipRes)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("Failed to QueryMembershipForUser")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		// If the user has never been in the room then stop at this point.
 		// We won't tell the user about a room they have never joined.
 		if !membershipRes.HasBeenInRoom {
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden(fmt.Sprintf("Unknown room %q or user %q has never joined this room", roomID, device.UserID)),
+				JSON: spec.Forbidden(fmt.Sprintf("Unknown room %q or user %q has never joined this room", roomID, device.UserID)),
 			}
 		}
 		// Otherwise, if the user has been in the room, whether or not we
@@ -148,7 +147,7 @@ func OnIncomingStateRequest(ctx context.Context, device *userapi.Device, rsAPI a
 		}, &stateAfterRes)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("Failed to QueryMembershipForUser")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		for _, ev := range stateAfterRes.StateEvents {
 			stateEvents = append(
@@ -203,7 +202,7 @@ func OnIncomingStateTypeRequest(
 		StateToFetch: stateToFetch,
 	}, &stateRes); err != nil {
 		util.GetLogger(ctx).WithError(err).Error("queryAPI.QueryLatestEventsAndState failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// Look at the room state and see if we have a history visibility event
@@ -214,7 +213,7 @@ func OnIncomingStateTypeRequest(
 			content := map[string]string{}
 			if err := json.Unmarshal(ev.Content(), &content); err != nil {
 				util.GetLogger(ctx).WithError(err).Error("json.Unmarshal for history visibility failed")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 			if visibility, ok := content["history_visibility"]; ok {
 				worldReadable = visibility == "world_readable"
@@ -240,14 +239,14 @@ func OnIncomingStateTypeRequest(
 		}, &membershipRes)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("Failed to QueryMembershipForUser")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		// If the user has never been in the room then stop at this point.
 		// We won't tell the user about a room they have never joined.
 		if !membershipRes.HasBeenInRoom || membershipRes.Membership == spec.Ban {
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden(fmt.Sprintf("Unknown room %q or user %q has never joined this room", roomID, device.UserID)),
+				JSON: spec.Forbidden(fmt.Sprintf("Unknown room %q or user %q has never joined this room", roomID, device.UserID)),
 			}
 		}
 		// Otherwise, if the user has been in the room, whether or not we
@@ -295,7 +294,7 @@ func OnIncomingStateTypeRequest(
 		}, &stateAfterRes)
 		if err != nil {
 			util.GetLogger(ctx).WithError(err).Error("Failed to QueryMembershipForUser")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		if len(stateAfterRes.StateEvents) > 0 {
 			event = stateAfterRes.StateEvents[0]
@@ -307,7 +306,7 @@ func OnIncomingStateTypeRequest(
 	if event == nil {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(fmt.Sprintf("Cannot find state event for %q", evType)),
+			JSON: spec.NotFound(fmt.Sprintf("Cannot find state event for %q", evType)),
 		}
 	}
 
diff --git a/clientapi/routing/thirdparty.go b/clientapi/routing/thirdparty.go
index 7a62da44..0ee21855 100644
--- a/clientapi/routing/thirdparty.go
+++ b/clientapi/routing/thirdparty.go
@@ -21,8 +21,8 @@ import (
 	"github.com/matrix-org/util"
 
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 // Protocols implements
@@ -33,13 +33,13 @@ func Protocols(req *http.Request, asAPI appserviceAPI.AppServiceInternalAPI, dev
 	resp := &appserviceAPI.ProtocolResponse{}
 
 	if err := asAPI.Protocols(req.Context(), &appserviceAPI.ProtocolRequest{Protocol: protocol}, resp); err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !resp.Exists {
 		if protocol != "" {
 			return util.JSONResponse{
 				Code: http.StatusNotFound,
-				JSON: jsonerror.NotFound("The protocol is unknown."),
+				JSON: spec.NotFound("The protocol is unknown."),
 			}
 		}
 		return util.JSONResponse{
@@ -71,12 +71,12 @@ func User(req *http.Request, asAPI appserviceAPI.AppServiceInternalAPI, device *
 		Protocol: protocol,
 		Params:   params.Encode(),
 	}, resp); err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !resp.Exists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("The Matrix User ID was not found"),
+			JSON: spec.NotFound("The Matrix User ID was not found"),
 		}
 	}
 	return util.JSONResponse{
@@ -97,12 +97,12 @@ func Location(req *http.Request, asAPI appserviceAPI.AppServiceInternalAPI, devi
 		Protocol: protocol,
 		Params:   params.Encode(),
 	}, resp); err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !resp.Exists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("No portal rooms were found."),
+			JSON: spec.NotFound("No portal rooms were found."),
 		}
 	}
 	return util.JSONResponse{
diff --git a/clientapi/routing/threepid.go b/clientapi/routing/threepid.go
index 102b1d1c..64fa59e4 100644
--- a/clientapi/routing/threepid.go
+++ b/clientapi/routing/threepid.go
@@ -19,12 +19,12 @@ import (
 
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/clientapi/threepid"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
 	userdb "github.com/matrix-org/dendrite/userapi/storage"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
@@ -60,13 +60,13 @@ func RequestEmailToken(req *http.Request, threePIDAPI api.ClientUserAPI, cfg *co
 
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("threePIDAPI.QueryLocalpartForThreePID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if len(res.Localpart) > 0 {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MatrixError{
+			JSON: spec.MatrixError{
 				ErrCode: "M_THREEPID_IN_USE",
 				Err:     userdb.Err3PIDInUse.Error(),
 			},
@@ -77,11 +77,11 @@ func RequestEmailToken(req *http.Request, threePIDAPI api.ClientUserAPI, cfg *co
 	if err == threepid.ErrNotTrusted {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotTrusted(body.IDServer),
+			JSON: spec.NotTrusted(body.IDServer),
 		}
 	} else if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("threepid.CreateSession failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -105,17 +105,17 @@ func CheckAndSave3PIDAssociation(
 	if err == threepid.ErrNotTrusted {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotTrusted(body.Creds.IDServer),
+			JSON: spec.NotTrusted(body.Creds.IDServer),
 		}
 	} else if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("threepid.CheckAssociation failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if !verified {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MatrixError{
+			JSON: spec.MatrixError{
 				ErrCode: "M_THREEPID_AUTH_FAILED",
 				Err:     "Failed to auth 3pid",
 			},
@@ -127,7 +127,7 @@ func CheckAndSave3PIDAssociation(
 		err = threepid.PublishAssociation(req.Context(), body.Creds, device.UserID, cfg, client)
 		if err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("threepid.PublishAssociation failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
@@ -135,7 +135,7 @@ func CheckAndSave3PIDAssociation(
 	localpart, domain, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if err = threePIDAPI.PerformSaveThreePIDAssociation(req.Context(), &api.PerformSaveThreePIDAssociationRequest{
@@ -145,7 +145,7 @@ func CheckAndSave3PIDAssociation(
 		Medium:     medium,
 	}, &struct{}{}); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("threePIDAPI.PerformSaveThreePIDAssociation failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -161,7 +161,7 @@ func GetAssociated3PIDs(
 	localpart, domain, err := gomatrixserverlib.SplitID('@', device.UserID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	res := &api.QueryThreePIDsForLocalpartResponse{}
@@ -171,7 +171,7 @@ func GetAssociated3PIDs(
 	}, res)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("threepidAPI.QueryThreePIDsForLocalpart failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -192,7 +192,7 @@ func Forget3PID(req *http.Request, threepidAPI api.ClientUserAPI) util.JSONRespo
 		Medium:   body.Medium,
 	}, &struct{}{}); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("threepidAPI.PerformForgetThreePID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/upgrade_room.go b/clientapi/routing/upgrade_room.go
index f0936db1f..43f8d3e2 100644
--- a/clientapi/routing/upgrade_room.go
+++ b/clientapi/routing/upgrade_room.go
@@ -20,13 +20,13 @@ import (
 
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/version"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -55,7 +55,7 @@ func UpgradeRoom(
 	if _, err := version.SupportedRoomVersion(gomatrixserverlib.RoomVersion(r.NewVersion)); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UnsupportedRoomVersion("This server does not support that room version"),
+			JSON: spec.UnsupportedRoomVersion("This server does not support that room version"),
 		}
 	}
 
@@ -65,16 +65,16 @@ func UpgradeRoom(
 	case roomserverAPI.ErrNotAllowed:
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(e.Error()),
+			JSON: spec.Forbidden(e.Error()),
 		}
 	default:
 		if errors.Is(err, eventutil.ErrRoomNoExists) {
 			return util.JSONResponse{
 				Code: http.StatusNotFound,
-				JSON: jsonerror.NotFound("Room does not exist"),
+				JSON: spec.NotFound("Room does not exist"),
 			}
 		}
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/clientapi/routing/voip.go b/clientapi/routing/voip.go
index f0f69ce3..f3db0cbe 100644
--- a/clientapi/routing/voip.go
+++ b/clientapi/routing/voip.go
@@ -25,9 +25,9 @@ import (
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/util"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 // RequestTurnServer implements:
@@ -60,7 +60,7 @@ func RequestTurnServer(req *http.Request, device *api.Device, cfg *config.Client
 
 		if err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("mac.Write failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		resp.Password = base64.StdEncoding.EncodeToString(mac.Sum(nil))
diff --git a/federationapi/federationapi_test.go b/federationapi/federationapi_test.go
index bd49c530..beb648a4 100644
--- a/federationapi/federationapi_test.go
+++ b/federationapi/federationapi_test.go
@@ -37,12 +37,11 @@ type fedRoomserverAPI struct {
 }
 
 // PerformJoin will call this function
-func (f *fedRoomserverAPI) InputRoomEvents(ctx context.Context, req *rsapi.InputRoomEventsRequest, res *rsapi.InputRoomEventsResponse) error {
+func (f *fedRoomserverAPI) InputRoomEvents(ctx context.Context, req *rsapi.InputRoomEventsRequest, res *rsapi.InputRoomEventsResponse) {
 	if f.inputRoomEvents == nil {
-		return nil
+		return
 	}
 	f.inputRoomEvents(ctx, req, res)
-	return nil
 }
 
 // keychange consumer calls this
diff --git a/federationapi/routing/backfill.go b/federationapi/routing/backfill.go
index 05488af6..81b61322 100644
--- a/federationapi/routing/backfill.go
+++ b/federationapi/routing/backfill.go
@@ -21,7 +21,6 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/setup/config"
@@ -50,7 +49,7 @@ func Backfill(
 	if _, _, err = gomatrixserverlib.SplitID('!', roomID); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Bad room ID: " + err.Error()),
+			JSON: spec.MissingParam("Bad room ID: " + err.Error()),
 		}
 	}
 
@@ -65,14 +64,14 @@ func Backfill(
 	if !exists {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("v is missing"),
+			JSON: spec.MissingParam("v is missing"),
 		}
 	}
 	limit = httpReq.URL.Query().Get("limit")
 	if len(limit) == 0 {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("limit is missing"),
+			JSON: spec.MissingParam("limit is missing"),
 		}
 	}
 
@@ -92,14 +91,14 @@ func Backfill(
 		util.GetLogger(httpReq.Context()).WithError(err).Error("strconv.Atoi failed")
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(fmt.Sprintf("limit %q is invalid format", limit)),
+			JSON: spec.InvalidParam(fmt.Sprintf("limit %q is invalid format", limit)),
 		}
 	}
 
 	// Query the roomserver.
 	if err = rsAPI.PerformBackfill(httpReq.Context(), &req, &res); err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("query.PerformBackfill failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// Filter any event that's not from the requested room out.
diff --git a/federationapi/routing/devices.go b/federationapi/routing/devices.go
index 6a2ef152..318c0a34 100644
--- a/federationapi/routing/devices.go
+++ b/federationapi/routing/devices.go
@@ -16,7 +16,6 @@ import (
 	"encoding/json"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
@@ -39,7 +38,7 @@ func GetUserDevices(
 	}
 	if res.Error != nil {
 		util.GetLogger(req.Context()).WithError(res.Error).Error("keyAPI.QueryDeviceMessages failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	sigReq := &api.QuerySignaturesRequest{
@@ -51,9 +50,7 @@ func GetUserDevices(
 	for _, dev := range res.Devices {
 		sigReq.TargetIDs[userID] = append(sigReq.TargetIDs[userID], gomatrixserverlib.KeyID(dev.DeviceID))
 	}
-	if err := keyAPI.QuerySignatures(req.Context(), sigReq, sigRes); err != nil {
-		return jsonerror.InternalAPIError(req.Context(), err)
-	}
+	keyAPI.QuerySignatures(req.Context(), sigReq, sigRes)
 
 	response := fclient.RespUserDevices{
 		UserID:   userID,
diff --git a/federationapi/routing/eventauth.go b/federationapi/routing/eventauth.go
index da1e77d8..ca279ac2 100644
--- a/federationapi/routing/eventauth.go
+++ b/federationapi/routing/eventauth.go
@@ -16,10 +16,10 @@ import (
 	"context"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -43,7 +43,7 @@ func GetEventAuth(
 	}
 
 	if event.RoomID() != roomID {
-		return util.JSONResponse{Code: http.StatusNotFound, JSON: jsonerror.NotFound("event does not belong to this room")}
+		return util.JSONResponse{Code: http.StatusNotFound, JSON: spec.NotFound("event does not belong to this room")}
 	}
 	resErr = allowedToSeeEvent(ctx, request.Origin(), rsAPI, eventID)
 	if resErr != nil {
diff --git a/federationapi/routing/events.go b/federationapi/routing/events.go
index efd64dce..196a54db 100644
--- a/federationapi/routing/events.go
+++ b/federationapi/routing/events.go
@@ -20,13 +20,11 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
-
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
-	"github.com/matrix-org/dendrite/roomserver/api"
 )
 
 // GetEvent returns the requested event
@@ -95,7 +93,7 @@ func fetchEvent(ctx context.Context, rsAPI api.FederationRoomserverAPI, roomID,
 	if len(eventsResponse.Events) == 0 {
 		return nil, &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Event not found"),
+			JSON: spec.NotFound("Event not found"),
 		}
 	}
 
diff --git a/federationapi/routing/invite.go b/federationapi/routing/invite.go
index 0fcb6414..bdfe2c82 100644
--- a/federationapi/routing/invite.go
+++ b/federationapi/routing/invite.go
@@ -21,12 +21,12 @@ import (
 	"net/http"
 
 	"github.com/getsentry/sentry-go"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -46,14 +46,14 @@ func InviteV2(
 	case gomatrixserverlib.UnsupportedRoomVersionError:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UnsupportedRoomVersion(
+			JSON: spec.UnsupportedRoomVersion(
 				fmt.Sprintf("Room version %q is not supported by this server.", e.Version),
 			),
 		}
 	case gomatrixserverlib.BadJSONError:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	case nil:
 		return processInvite(
@@ -62,7 +62,7 @@ func InviteV2(
 	default:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("The request body could not be decoded into an invite request. " + err.Error()),
+			JSON: spec.NotJSON("The request body could not be decoded into an invite request. " + err.Error()),
 		}
 	}
 }
@@ -85,13 +85,13 @@ func InviteV1(
 	case gomatrixserverlib.BadJSONError:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	case nil:
 	default:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("The request body could not be decoded into an invite v1 request. " + err.Error()),
+			JSON: spec.NotJSON("The request body could not be decoded into an invite v1 request. " + err.Error()),
 		}
 	}
 	var strippedState []fclient.InviteV2StrippedState
@@ -122,7 +122,7 @@ func processInvite(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UnsupportedRoomVersion(
+			JSON: spec.UnsupportedRoomVersion(
 				fmt.Sprintf("Room version %q is not supported by this server.", roomVer),
 			),
 		}
@@ -132,7 +132,7 @@ func processInvite(
 	if event.RoomID() != roomID {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The room ID in the request path must match the room ID in the invite event JSON"),
+			JSON: spec.BadJSON("The room ID in the request path must match the room ID in the invite event JSON"),
 		}
 	}
 
@@ -140,14 +140,14 @@ func processInvite(
 	if event.EventID() != eventID {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event ID in the request path must match the event ID in the invite event JSON"),
+			JSON: spec.BadJSON("The event ID in the request path must match the event ID in the invite event JSON"),
 		}
 	}
 
 	if event.StateKey() == nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The invite event has no state key"),
+			JSON: spec.BadJSON("The invite event has no state key"),
 		}
 	}
 
@@ -155,7 +155,7 @@ func processInvite(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(fmt.Sprintf("The user ID is invalid or domain %q does not belong to this server", domain)),
+			JSON: spec.InvalidParam(fmt.Sprintf("The user ID is invalid or domain %q does not belong to this server", domain)),
 		}
 	}
 
@@ -164,14 +164,14 @@ func processInvite(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event JSON could not be redacted"),
+			JSON: spec.BadJSON("The event JSON could not be redacted"),
 		}
 	}
 	_, serverName, err := gomatrixserverlib.SplitID('@', event.Sender())
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event JSON contains an invalid sender"),
+			JSON: spec.BadJSON("The event JSON contains an invalid sender"),
 		}
 	}
 	verifyRequests := []gomatrixserverlib.VerifyJSONRequest{{
@@ -183,12 +183,12 @@ func processInvite(
 	verifyResults, err := keys.VerifyJSONs(ctx, verifyRequests)
 	if err != nil {
 		util.GetLogger(ctx).WithError(err).Error("keys.VerifyJSONs failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if verifyResults[0].Error != nil {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The invite must be signed by the server it originated on"),
+			JSON: spec.Forbidden("The invite must be signed by the server it originated on"),
 		}
 	}
 
@@ -211,7 +211,7 @@ func processInvite(
 		util.GetLogger(ctx).WithError(err).Error("PerformInvite failed")
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
@@ -219,12 +219,12 @@ func processInvite(
 	case api.ErrInvalidID:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(e.Error()),
+			JSON: spec.Unknown(e.Error()),
 		}
 	case api.ErrNotAllowed:
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(e.Error()),
+			JSON: spec.Forbidden(e.Error()),
 		}
 	case nil:
 	default:
@@ -232,7 +232,7 @@ func processInvite(
 		sentry.CaptureException(err)
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
diff --git a/federationapi/routing/join.go b/federationapi/routing/join.go
index c68a6f0c..c301785c 100644
--- a/federationapi/routing/join.go
+++ b/federationapi/routing/join.go
@@ -27,7 +27,6 @@ import (
 	"github.com/matrix-org/util"
 	"github.com/sirupsen/logrus"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
@@ -47,7 +46,7 @@ func MakeJoin(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
@@ -66,7 +65,7 @@ func MakeJoin(
 	if !remoteSupportsVersion {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.IncompatibleRoomVersion(roomVersion),
+			JSON: spec.IncompatibleRoomVersion(string(roomVersion)),
 		}
 	}
 
@@ -74,13 +73,13 @@ func MakeJoin(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Invalid UserID"),
+			JSON: spec.BadJSON("Invalid UserID"),
 		}
 	}
 	if domain != request.Origin() {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The join must be sent by the server of the user"),
+			JSON: spec.Forbidden("The join must be sent by the server of the user"),
 		}
 	}
 
@@ -92,18 +91,18 @@ func MakeJoin(
 	inRoomRes := &api.QueryServerJoinedToRoomResponse{}
 	if err = rsAPI.QueryServerJoinedToRoom(httpReq.Context(), inRoomReq, inRoomRes); err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("rsAPI.QueryServerJoinedToRoom failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !inRoomRes.RoomExists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(fmt.Sprintf("Room ID %q was not found on this server", roomID)),
+			JSON: spec.NotFound(fmt.Sprintf("Room ID %q was not found on this server", roomID)),
 		}
 	}
 	if !inRoomRes.IsInRoom {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(fmt.Sprintf("Room ID %q has no remaining users on this server", roomID)),
+			JSON: spec.NotFound(fmt.Sprintf("Room ID %q has no remaining users on this server", roomID)),
 		}
 	}
 
@@ -112,7 +111,7 @@ func MakeJoin(
 	res, authorisedVia, err := checkRestrictedJoin(httpReq, rsAPI, roomVersion, roomID, userID)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("checkRestrictedJoin failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	} else if res != nil {
 		return *res
 	}
@@ -130,14 +129,14 @@ func MakeJoin(
 	}
 	if err = proto.SetContent(content); err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("builder.SetContent failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	identity, err := cfg.Matrix.SigningIdentityFor(request.Destination())
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(
+			JSON: spec.NotFound(
 				fmt.Sprintf("Server name %q does not exist", request.Destination()),
 			),
 		}
@@ -150,16 +149,16 @@ func MakeJoin(
 	if err == eventutil.ErrRoomNoExists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Room does not exist"),
+			JSON: spec.NotFound("Room does not exist"),
 		}
 	} else if e, ok := err.(gomatrixserverlib.BadJSONError); ok {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(e.Error()),
+			JSON: spec.BadJSON(e.Error()),
 		}
 	} else if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("eventutil.BuildEvent failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// Check that the join is allowed or not
@@ -172,7 +171,7 @@ func MakeJoin(
 	if err = gomatrixserverlib.Allowed(event.PDU, &provider); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(err.Error()),
+			JSON: spec.Forbidden(err.Error()),
 		}
 	}
 
@@ -202,14 +201,14 @@ func SendJoin(
 		util.GetLogger(httpReq.Context()).WithError(err).Error("rsAPI.QueryRoomVersionForRoom failed")
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 	verImpl, err := gomatrixserverlib.GetRoomVersion(roomVersion)
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.UnsupportedRoomVersion(
+			JSON: spec.UnsupportedRoomVersion(
 				fmt.Sprintf("QueryRoomVersionForRoom returned unknown room version: %s", roomVersion),
 			),
 		}
@@ -219,7 +218,7 @@ func SendJoin(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be decoded into valid JSON: " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be decoded into valid JSON: " + err.Error()),
 		}
 	}
 
@@ -227,13 +226,13 @@ func SendJoin(
 	if event.StateKey() == nil || event.StateKeyEquals("") {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("No state key was provided in the join event."),
+			JSON: spec.BadJSON("No state key was provided in the join event."),
 		}
 	}
 	if !event.StateKeyEquals(event.Sender()) {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Event state key must match the event sender."),
+			JSON: spec.BadJSON("Event state key must match the event sender."),
 		}
 	}
 
@@ -244,12 +243,12 @@ func SendJoin(
 	if _, serverName, err = gomatrixserverlib.SplitID('@', event.Sender()); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The sender of the join is invalid"),
+			JSON: spec.Forbidden("The sender of the join is invalid"),
 		}
 	} else if serverName != request.Origin() {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The sender does not match the server that originated the request"),
+			JSON: spec.Forbidden("The sender does not match the server that originated the request"),
 		}
 	}
 
@@ -257,7 +256,7 @@ func SendJoin(
 	if event.RoomID() != roomID {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(
+			JSON: spec.BadJSON(
 				fmt.Sprintf(
 					"The room ID in the request path (%q) must match the room ID in the join event JSON (%q)",
 					roomID, event.RoomID(),
@@ -270,7 +269,7 @@ func SendJoin(
 	if event.EventID() != eventID {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(
+			JSON: spec.BadJSON(
 				fmt.Sprintf(
 					"The event ID in the request path (%q) must match the event ID in the join event JSON (%q)",
 					eventID, event.EventID(),
@@ -284,13 +283,13 @@ func SendJoin(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("missing content.membership key"),
+			JSON: spec.BadJSON("missing content.membership key"),
 		}
 	}
 	if membership != spec.Join {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("membership must be 'join'"),
+			JSON: spec.BadJSON("membership must be 'join'"),
 		}
 	}
 
@@ -300,7 +299,7 @@ func SendJoin(
 		logrus.WithError(err).Errorf("XXX: join.go")
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event JSON could not be redacted"),
+			JSON: spec.BadJSON("The event JSON could not be redacted"),
 		}
 	}
 	verifyRequests := []gomatrixserverlib.VerifyJSONRequest{{
@@ -312,12 +311,12 @@ func SendJoin(
 	verifyResults, err := keys.VerifyJSONs(httpReq.Context(), verifyRequests)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("keys.VerifyJSONs failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if verifyResults[0].Error != nil {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Signature check failed: " + verifyResults[0].Error.Error()),
+			JSON: spec.Forbidden("Signature check failed: " + verifyResults[0].Error.Error()),
 		}
 	}
 
@@ -332,19 +331,19 @@ func SendJoin(
 	}, &stateAndAuthChainResponse)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("rsAPI.QueryStateAndAuthChain failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if !stateAndAuthChainResponse.RoomExists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Room does not exist"),
+			JSON: spec.NotFound("Room does not exist"),
 		}
 	}
 	if !stateAndAuthChainResponse.StateKnown {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("State not known"),
+			JSON: spec.Forbidden("State not known"),
 		}
 	}
 
@@ -367,7 +366,7 @@ func SendJoin(
 	if isBanned {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("user is banned"),
+			JSON: spec.Forbidden("user is banned"),
 		}
 	}
 
@@ -377,7 +376,7 @@ func SendJoin(
 	if err := json.Unmarshal(event.Content(), &memberContent); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	}
 	if memberContent.AuthorisedVia != "" {
@@ -385,13 +384,13 @@ func SendJoin(
 		if err != nil {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON(fmt.Sprintf("The authorising username %q is invalid.", memberContent.AuthorisedVia)),
+				JSON: spec.BadJSON(fmt.Sprintf("The authorising username %q is invalid.", memberContent.AuthorisedVia)),
 			}
 		}
 		if domain != cfg.Matrix.ServerName {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON(fmt.Sprintf("The authorising username %q does not belong to this server.", memberContent.AuthorisedVia)),
+				JSON: spec.BadJSON(fmt.Sprintf("The authorising username %q does not belong to this server.", memberContent.AuthorisedVia)),
 			}
 		}
 	}
@@ -410,7 +409,7 @@ func SendJoin(
 	// the room, so set SendAsServer to cfg.Matrix.ServerName
 	if !alreadyJoined {
 		var response api.InputRoomEventsResponse
-		if err := rsAPI.InputRoomEvents(httpReq.Context(), &api.InputRoomEventsRequest{
+		rsAPI.InputRoomEvents(httpReq.Context(), &api.InputRoomEventsRequest{
 			InputRoomEvents: []api.InputRoomEvent{
 				{
 					Kind:          api.KindNew,
@@ -419,18 +418,16 @@ func SendJoin(
 					TransactionID: nil,
 				},
 			},
-		}, &response); err != nil {
-			return jsonerror.InternalAPIError(httpReq.Context(), err)
-		}
+		}, &response)
 		if response.ErrMsg != "" {
 			util.GetLogger(httpReq.Context()).WithField(logrus.ErrorKey, response.ErrMsg).Error("SendEvents failed")
 			if response.NotAllowed {
 				return util.JSONResponse{
 					Code: http.StatusBadRequest,
-					JSON: jsonerror.Forbidden(response.ErrMsg),
+					JSON: spec.Forbidden(response.ErrMsg),
 				}
 			}
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
@@ -498,7 +495,7 @@ func checkRestrictedJoin(
 		// instead.
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UnableToAuthoriseJoin("This server cannot authorise the join."),
+			JSON: spec.UnableToAuthoriseJoin("This server cannot authorise the join."),
 		}, "", nil
 
 	case !res.Allowed:
@@ -507,7 +504,7 @@ func checkRestrictedJoin(
 		// and therefore can't join this room.
 		return &util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You are not joined to any matching rooms."),
+			JSON: spec.Forbidden("You are not joined to any matching rooms."),
 		}, "", nil
 
 	default:
diff --git a/federationapi/routing/keys.go b/federationapi/routing/keys.go
index 6c30e5b0..d85de73d 100644
--- a/federationapi/routing/keys.go
+++ b/federationapi/routing/keys.go
@@ -20,7 +20,6 @@ import (
 	"time"
 
 	clienthttputil "github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	federationAPI "github.com/matrix-org/dendrite/federationapi/api"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/userapi/api"
@@ -46,7 +45,7 @@ func QueryDeviceKeys(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 	// make sure we only query users on our domain
@@ -63,14 +62,12 @@ func QueryDeviceKeys(
 	}
 
 	var queryRes api.QueryKeysResponse
-	if err := keyAPI.QueryKeys(httpReq.Context(), &api.QueryKeysRequest{
+	keyAPI.QueryKeys(httpReq.Context(), &api.QueryKeysRequest{
 		UserToDevices: qkr.DeviceKeys,
-	}, &queryRes); err != nil {
-		return jsonerror.InternalAPIError(httpReq.Context(), err)
-	}
+	}, &queryRes)
 	if queryRes.Error != nil {
 		util.GetLogger(httpReq.Context()).WithError(queryRes.Error).Error("Failed to QueryKeys")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	return util.JSONResponse{
 		Code: 200,
@@ -100,7 +97,7 @@ func ClaimOneTimeKeys(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 	// make sure we only claim users on our domain
@@ -117,14 +114,12 @@ func ClaimOneTimeKeys(
 	}
 
 	var claimRes api.PerformClaimKeysResponse
-	if err := keyAPI.PerformClaimKeys(httpReq.Context(), &api.PerformClaimKeysRequest{
+	keyAPI.PerformClaimKeys(httpReq.Context(), &api.PerformClaimKeysRequest{
 		OneTimeKeys: cor.OneTimeKeys,
-	}, &claimRes); err != nil {
-		return jsonerror.InternalAPIError(httpReq.Context(), err)
-	}
+	}, &claimRes)
 	if claimRes.Error != nil {
 		util.GetLogger(httpReq.Context()).WithError(claimRes.Error).Error("Failed to PerformClaimKeys")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	return util.JSONResponse{
 		Code: 200,
@@ -205,7 +200,7 @@ func NotaryKeys(
 	if !cfg.Matrix.IsLocalServerName(serverName) {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Server name not known"),
+			JSON: spec.NotFound("Server name not known"),
 		}
 	}
 
@@ -248,7 +243,7 @@ func NotaryKeys(
 			j, err := json.Marshal(keys)
 			if err != nil {
 				logrus.WithError(err).Errorf("Failed to marshal %q response", serverName)
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 
 			js, err := gomatrixserverlib.SignJSON(
@@ -256,7 +251,7 @@ func NotaryKeys(
 			)
 			if err != nil {
 				logrus.WithError(err).Errorf("Failed to sign %q response", serverName)
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 
 			response.ServerKeys = append(response.ServerKeys, js)
diff --git a/federationapi/routing/leave.go b/federationapi/routing/leave.go
index f4936d4a..fdfbf15d 100644
--- a/federationapi/routing/leave.go
+++ b/federationapi/routing/leave.go
@@ -17,7 +17,6 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
@@ -41,13 +40,13 @@ func MakeLeave(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Invalid UserID"),
+			JSON: spec.BadJSON("Invalid UserID"),
 		}
 	}
 	if domain != request.Origin() {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The leave must be sent by the server of the user"),
+			JSON: spec.Forbidden("The leave must be sent by the server of the user"),
 		}
 	}
 
@@ -61,14 +60,14 @@ func MakeLeave(
 	err = proto.SetContent(map[string]interface{}{"membership": spec.Leave})
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("proto.SetContent failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	identity, err := cfg.Matrix.SigningIdentityFor(request.Destination())
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(
+			JSON: spec.NotFound(
 				fmt.Sprintf("Server name %q does not exist", request.Destination()),
 			),
 		}
@@ -79,16 +78,16 @@ func MakeLeave(
 	if err == eventutil.ErrRoomNoExists {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Room does not exist"),
+			JSON: spec.NotFound("Room does not exist"),
 		}
 	} else if e, ok := err.(gomatrixserverlib.BadJSONError); ok {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(e.Error()),
+			JSON: spec.BadJSON(e.Error()),
 		}
 	} else if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("eventutil.BuildEvent failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// If the user has already left then just return their last leave
@@ -118,7 +117,7 @@ func MakeLeave(
 	if err = gomatrixserverlib.Allowed(event, &provider); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden(err.Error()),
+			JSON: spec.Forbidden(err.Error()),
 		}
 	}
 
@@ -145,7 +144,7 @@ func SendLeave(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UnsupportedRoomVersion(err.Error()),
+			JSON: spec.UnsupportedRoomVersion(err.Error()),
 		}
 	}
 
@@ -153,7 +152,7 @@ func SendLeave(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.UnsupportedRoomVersion(
+			JSON: spec.UnsupportedRoomVersion(
 				fmt.Sprintf("QueryRoomVersionForRoom returned unknown version: %s", roomVersion),
 			),
 		}
@@ -165,13 +164,13 @@ func SendLeave(
 	case gomatrixserverlib.BadJSONError:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	case nil:
 	default:
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 
@@ -179,7 +178,7 @@ func SendLeave(
 	if event.RoomID() != roomID {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The room ID in the request path must match the room ID in the leave event JSON"),
+			JSON: spec.BadJSON("The room ID in the request path must match the room ID in the leave event JSON"),
 		}
 	}
 
@@ -187,20 +186,20 @@ func SendLeave(
 	if event.EventID() != eventID {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event ID in the request path must match the event ID in the leave event JSON"),
+			JSON: spec.BadJSON("The event ID in the request path must match the event ID in the leave event JSON"),
 		}
 	}
 
 	if event.StateKey() == nil || event.StateKeyEquals("") {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("No state key was provided in the leave event."),
+			JSON: spec.BadJSON("No state key was provided in the leave event."),
 		}
 	}
 	if !event.StateKeyEquals(event.Sender()) {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Event state key must match the event sender."),
+			JSON: spec.BadJSON("Event state key must match the event sender."),
 		}
 	}
 
@@ -211,12 +210,12 @@ func SendLeave(
 	if _, serverName, err = gomatrixserverlib.SplitID('@', event.Sender()); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The sender of the join is invalid"),
+			JSON: spec.Forbidden("The sender of the join is invalid"),
 		}
 	} else if serverName != request.Origin() {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The sender does not match the server that originated the request"),
+			JSON: spec.Forbidden("The sender does not match the server that originated the request"),
 		}
 	}
 
@@ -234,7 +233,7 @@ func SendLeave(
 	err = rsAPI.QueryLatestEventsAndState(httpReq.Context(), queryReq, queryRes)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("rsAPI.QueryLatestEventsAndState failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	// The room doesn't exist or we weren't ever joined to it. Might as well
 	// no-op here.
@@ -268,7 +267,7 @@ func SendLeave(
 		logrus.WithError(err).Errorf("XXX: leave.go")
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event JSON could not be redacted"),
+			JSON: spec.BadJSON("The event JSON could not be redacted"),
 		}
 	}
 	verifyRequests := []gomatrixserverlib.VerifyJSONRequest{{
@@ -280,12 +279,12 @@ func SendLeave(
 	verifyResults, err := keys.VerifyJSONs(httpReq.Context(), verifyRequests)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("keys.VerifyJSONs failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if verifyResults[0].Error != nil {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("The leave must be signed by the server it originated on"),
+			JSON: spec.Forbidden("The leave must be signed by the server it originated on"),
 		}
 	}
 
@@ -295,13 +294,13 @@ func SendLeave(
 		util.GetLogger(httpReq.Context()).WithError(err).Error("event.Membership failed")
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("missing content.membership key"),
+			JSON: spec.BadJSON("missing content.membership key"),
 		}
 	}
 	if mem != spec.Leave {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The membership in the event content must be set to leave"),
+			JSON: spec.BadJSON("The membership in the event content must be set to leave"),
 		}
 	}
 
@@ -309,7 +308,7 @@ func SendLeave(
 	// We are responsible for notifying other servers that the user has left
 	// the room, so set SendAsServer to cfg.Matrix.ServerName
 	var response api.InputRoomEventsResponse
-	if err := rsAPI.InputRoomEvents(httpReq.Context(), &api.InputRoomEventsRequest{
+	rsAPI.InputRoomEvents(httpReq.Context(), &api.InputRoomEventsRequest{
 		InputRoomEvents: []api.InputRoomEvent{
 			{
 				Kind:          api.KindNew,
@@ -318,19 +317,17 @@ func SendLeave(
 				TransactionID: nil,
 			},
 		},
-	}, &response); err != nil {
-		return jsonerror.InternalAPIError(httpReq.Context(), err)
-	}
+	}, &response)
 
 	if response.ErrMsg != "" {
 		util.GetLogger(httpReq.Context()).WithField(logrus.ErrorKey, response.ErrMsg).WithField("not_allowed", response.NotAllowed).Error("producer.SendEvents failed")
 		if response.NotAllowed {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.Forbidden(response.ErrMsg),
+				JSON: spec.Forbidden(response.ErrMsg),
 			}
 		}
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/federationapi/routing/missingevents.go b/federationapi/routing/missingevents.go
index 23a99bf0..f8dd9e4f 100644
--- a/federationapi/routing/missingevents.go
+++ b/federationapi/routing/missingevents.go
@@ -16,10 +16,10 @@ import (
 	"encoding/json"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -42,7 +42,7 @@ func GetMissingEvents(
 	if err := json.Unmarshal(request.Content(), &gme); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 
@@ -63,7 +63,7 @@ func GetMissingEvents(
 		&eventsResponse,
 	); err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("query.QueryMissingEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	eventsResponse.Events = filterEvents(eventsResponse.Events, roomID)
diff --git a/federationapi/routing/openid.go b/federationapi/routing/openid.go
index cbc75a9a..d28f319f 100644
--- a/federationapi/routing/openid.go
+++ b/federationapi/routing/openid.go
@@ -18,8 +18,8 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -36,7 +36,7 @@ func GetOpenIDUserInfo(
 	if len(token) == 0 {
 		return util.JSONResponse{
 			Code: http.StatusUnauthorized,
-			JSON: jsonerror.MissingArgument("access_token is missing"),
+			JSON: spec.MissingParam("access_token is missing"),
 		}
 	}
 
@@ -55,7 +55,7 @@ func GetOpenIDUserInfo(
 	nowMS := time.Now().UnixNano() / int64(time.Millisecond)
 	if openIDTokenAttrResponse.Sub == "" || nowMS > openIDTokenAttrResponse.ExpiresAtMS {
 		code = http.StatusUnauthorized
-		res = jsonerror.UnknownToken("Access Token unknown or expired")
+		res = spec.UnknownToken("Access Token unknown or expired")
 	}
 
 	return util.JSONResponse{
diff --git a/federationapi/routing/peek.go b/federationapi/routing/peek.go
index efc46146..9e924556 100644
--- a/federationapi/routing/peek.go
+++ b/federationapi/routing/peek.go
@@ -17,12 +17,12 @@ package routing
 import (
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -40,7 +40,7 @@ func Peek(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
@@ -58,7 +58,7 @@ func Peek(
 	if !remoteSupportsVersion {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.IncompatibleRoomVersion(roomVersion),
+			JSON: spec.IncompatibleRoomVersion(string(roomVersion)),
 		}
 	}
 
diff --git a/federationapi/routing/profile.go b/federationapi/routing/profile.go
index 55641b21..7d6cfcaa 100644
--- a/federationapi/routing/profile.go
+++ b/federationapi/routing/profile.go
@@ -18,10 +18,10 @@ import (
 	"fmt"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -37,7 +37,7 @@ func GetProfile(
 	if userID == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("The request body did not contain required argument 'user_id'."),
+			JSON: spec.MissingParam("The request body did not contain required argument 'user_id'."),
 		}
 	}
 
@@ -46,14 +46,14 @@ func GetProfile(
 		util.GetLogger(httpReq.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue(fmt.Sprintf("Domain %q does not match this server", domain)),
+			JSON: spec.InvalidParam(fmt.Sprintf("Domain %q does not match this server", domain)),
 		}
 	}
 
 	profile, err := userAPI.QueryProfile(httpReq.Context(), userID)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("userAPI.QueryProfile failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	var res interface{}
@@ -71,7 +71,7 @@ func GetProfile(
 			}
 		default:
 			code = http.StatusBadRequest
-			res = jsonerror.InvalidArgumentValue("The request body did not contain an allowed value of argument 'field'. Allowed values are either: 'avatar_url', 'displayname'.")
+			res = spec.InvalidParam("The request body did not contain an allowed value of argument 'field'. Allowed values are either: 'avatar_url', 'displayname'.")
 		}
 	} else {
 		res = eventutil.UserProfile{
diff --git a/federationapi/routing/publicrooms.go b/federationapi/routing/publicrooms.go
index 80343d93..59ff4eb2 100644
--- a/federationapi/routing/publicrooms.go
+++ b/federationapi/routing/publicrooms.go
@@ -12,7 +12,6 @@ import (
 	"github.com/matrix-org/util"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 )
 
@@ -40,7 +39,7 @@ func GetPostPublicRooms(req *http.Request, rsAPI roomserverAPI.FederationRoomser
 	}
 	response, err := publicRooms(req.Context(), request, rsAPI)
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	return util.JSONResponse{
 		Code: http.StatusOK,
@@ -107,7 +106,7 @@ func fillPublicRoomsReq(httpReq *http.Request, request *PublicRoomReq) *util.JSO
 		// In that case, we want to assign 0 so we ignore the error
 		if err != nil && len(httpReq.FormValue("limit")) > 0 {
 			util.GetLogger(httpReq.Context()).WithError(err).Error("strconv.Atoi failed")
-			reqErr := jsonerror.InternalServerError()
+			reqErr := spec.InternalServerError()
 			return &reqErr
 		}
 		request.Limit = int16(limit)
@@ -119,7 +118,7 @@ func fillPublicRoomsReq(httpReq *http.Request, request *PublicRoomReq) *util.JSO
 
 	return &util.JSONResponse{
 		Code: http.StatusMethodNotAllowed,
-		JSON: jsonerror.NotFound("Bad method"),
+		JSON: spec.NotFound("Bad method"),
 	}
 }
 
diff --git a/federationapi/routing/query.go b/federationapi/routing/query.go
index 61efd73f..233290e2 100644
--- a/federationapi/routing/query.go
+++ b/federationapi/routing/query.go
@@ -18,13 +18,13 @@ import (
 	"fmt"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	federationAPI "github.com/matrix-org/dendrite/federationapi/api"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -40,14 +40,14 @@ func RoomAliasToID(
 	if roomAlias == "" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Must supply room alias parameter."),
+			JSON: spec.BadJSON("Must supply room alias parameter."),
 		}
 	}
 	_, domain, err := gomatrixserverlib.SplitID('#', roomAlias)
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Room alias must be in the form '#localpart:domain'"),
+			JSON: spec.BadJSON("Room alias must be in the form '#localpart:domain'"),
 		}
 	}
 
@@ -61,7 +61,7 @@ func RoomAliasToID(
 		queryRes := &roomserverAPI.GetRoomIDForAliasResponse{}
 		if err = rsAPI.GetRoomIDForAlias(httpReq.Context(), queryReq, queryRes); err != nil {
 			util.GetLogger(httpReq.Context()).WithError(err).Error("aliasAPI.GetRoomIDForAlias failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		if queryRes.RoomID != "" {
@@ -69,7 +69,7 @@ func RoomAliasToID(
 			var serverQueryRes federationAPI.QueryJoinedHostServerNamesInRoomResponse
 			if err = senderAPI.QueryJoinedHostServerNamesInRoom(httpReq.Context(), &serverQueryReq, &serverQueryRes); err != nil {
 				util.GetLogger(httpReq.Context()).WithError(err).Error("senderAPI.QueryJoinedHostServerNamesInRoom failed")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 
 			resp = fclient.RespDirectory{
@@ -80,7 +80,7 @@ func RoomAliasToID(
 			// If no alias was found, return an error
 			return util.JSONResponse{
 				Code: http.StatusNotFound,
-				JSON: jsonerror.NotFound(fmt.Sprintf("Room alias %s not found", roomAlias)),
+				JSON: spec.NotFound(fmt.Sprintf("Room alias %s not found", roomAlias)),
 			}
 		}
 	} else {
@@ -91,14 +91,14 @@ func RoomAliasToID(
 				if x.Code == http.StatusNotFound {
 					return util.JSONResponse{
 						Code: http.StatusNotFound,
-						JSON: jsonerror.NotFound("Room alias not found"),
+						JSON: spec.NotFound("Room alias not found"),
 					}
 				}
 			}
 			// TODO: Return 502 if the remote server errored.
 			// TODO: Return 504 if the remote server timed out.
 			util.GetLogger(httpReq.Context()).WithError(err).Error("federation.LookupRoomAlias failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
diff --git a/federationapi/routing/routing.go b/federationapi/routing/routing.go
index 6ef544d0..f62a8f46 100644
--- a/federationapi/routing/routing.go
+++ b/federationapi/routing/routing.go
@@ -23,7 +23,6 @@ import (
 
 	"github.com/getsentry/sentry-go"
 	"github.com/gorilla/mux"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	fedInternal "github.com/matrix-org/dendrite/federationapi/internal"
 	"github.com/matrix-org/dendrite/federationapi/producers"
 	"github.com/matrix-org/dendrite/internal"
@@ -150,7 +149,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			return InviteV1(
@@ -166,7 +165,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			return InviteV2(
@@ -206,7 +205,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			return GetState(
@@ -221,7 +220,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			return GetStateIDs(
@@ -236,7 +235,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			return GetEventAuth(
@@ -279,7 +278,7 @@ func Setup(
 				if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 					return util.JSONResponse{
 						Code: http.StatusForbidden,
-						JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+						JSON: spec.Forbidden("Forbidden by server ACLs"),
 					}
 				}
 				roomID := vars["roomID"]
@@ -310,7 +309,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			roomID := vars["roomID"]
@@ -341,7 +340,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			roomID := vars["roomID"]
@@ -354,7 +353,7 @@ func Setup(
 			body = []interface{}{
 				res.Code, res.JSON,
 			}
-			jerr, ok := res.JSON.(*jsonerror.MatrixError)
+			jerr, ok := res.JSON.(*spec.MatrixError)
 			if ok {
 				body = jerr
 			}
@@ -373,7 +372,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			roomID := vars["roomID"]
@@ -390,7 +389,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			roomID := vars["roomID"]
@@ -407,7 +406,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			roomID := vars["roomID"]
@@ -420,7 +419,7 @@ func Setup(
 			body = []interface{}{
 				res.Code, res.JSON,
 			}
-			jerr, ok := res.JSON.(*jsonerror.MatrixError)
+			jerr, ok := res.JSON.(*spec.MatrixError)
 			if ok {
 				body = jerr
 			}
@@ -439,7 +438,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			roomID := vars["roomID"]
@@ -463,7 +462,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			return GetMissingEvents(httpReq, request, rsAPI, vars["roomID"])
@@ -476,7 +475,7 @@ func Setup(
 			if roomserverAPI.IsServerBannedFromRoom(httpReq.Context(), rsAPI, vars["roomID"], request.Origin()) {
 				return util.JSONResponse{
 					Code: http.StatusForbidden,
-					JSON: jsonerror.Forbidden("Forbidden by server ACLs"),
+					JSON: spec.Forbidden("Forbidden by server ACLs"),
 				}
 			}
 			return Backfill(httpReq, request, rsAPI, vars["roomID"], cfg)
@@ -528,7 +527,7 @@ func ErrorIfLocalServerNotInRoom(
 	if !joinedRes.IsInRoom {
 		return &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(fmt.Sprintf("This server is not joined to room %s", roomID)),
+			JSON: spec.NotFound(fmt.Sprintf("This server is not joined to room %s", roomID)),
 		}
 	}
 	return nil
diff --git a/federationapi/routing/send.go b/federationapi/routing/send.go
index 04bf505a..3c8e0cbe 100644
--- a/federationapi/routing/send.go
+++ b/federationapi/routing/send.go
@@ -25,12 +25,12 @@ import (
 	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/matrix-org/util"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/federationapi/producers"
 	"github.com/matrix-org/dendrite/internal"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
 	userAPI "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 const (
@@ -104,7 +104,7 @@ func Send(
 	if err := json.Unmarshal(request.Content(), &txnEvents); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 	// Transactions are limited in size; they can have at most 50 PDUs and 100 EDUs.
@@ -112,7 +112,7 @@ func Send(
 	if len(txnEvents.PDUs) > 50 || len(txnEvents.EDUs) > 100 {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("max 50 pdus / 100 edus"),
+			JSON: spec.BadJSON("max 50 pdus / 100 edus"),
 		}
 	}
 
diff --git a/federationapi/routing/state.go b/federationapi/routing/state.go
index aa2cb283..fa0e9351 100644
--- a/federationapi/routing/state.go
+++ b/federationapi/routing/state.go
@@ -17,10 +17,10 @@ import (
 	"net/http"
 	"net/url"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -88,7 +88,7 @@ func parseEventIDParam(
 	if eventID == "" {
 		resErr = &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("event_id missing"),
+			JSON: spec.MissingParam("event_id missing"),
 		}
 	}
 
@@ -114,7 +114,7 @@ func getState(
 	}
 
 	if event.RoomID() != roomID {
-		return nil, nil, &util.JSONResponse{Code: http.StatusNotFound, JSON: jsonerror.NotFound("event does not belong to this room")}
+		return nil, nil, &util.JSONResponse{Code: http.StatusNotFound, JSON: spec.NotFound("event does not belong to this room")}
 	}
 	resErr = allowedToSeeEvent(ctx, request.Origin(), rsAPI, eventID)
 	if resErr != nil {
@@ -140,17 +140,17 @@ func getState(
 	case !response.RoomExists:
 		return nil, nil, &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Room not found"),
+			JSON: spec.NotFound("Room not found"),
 		}
 	case !response.StateKnown:
 		return nil, nil, &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("State not known"),
+			JSON: spec.NotFound("State not known"),
 		}
 	case response.IsRejected:
 		return nil, nil, &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Event not found"),
+			JSON: spec.NotFound("Event not found"),
 		}
 	}
 
diff --git a/federationapi/routing/threepid.go b/federationapi/routing/threepid.go
index 244553ba..adfafe74 100644
--- a/federationapi/routing/threepid.go
+++ b/federationapi/routing/threepid.go
@@ -22,17 +22,14 @@ import (
 	"time"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/roomserver/types"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/matrix-org/gomatrixserverlib/spec"
-
-	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/util"
-
 	"github.com/sirupsen/logrus"
 )
 
@@ -74,7 +71,7 @@ func CreateInvitesFrom3PIDInvites(
 		if err != nil {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.UnsupportedRoomVersion(err.Error()),
+				JSON: spec.UnsupportedRoomVersion(err.Error()),
 			}
 		}
 
@@ -83,7 +80,7 @@ func CreateInvitesFrom3PIDInvites(
 		)
 		if err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("createInviteFrom3PIDInvite failed")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		if event != nil {
 			evs = append(evs, &types.HeaderedEvent{PDU: event})
@@ -103,7 +100,7 @@ func CreateInvitesFrom3PIDInvites(
 		false,
 	); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
@@ -125,7 +122,7 @@ func ExchangeThirdPartyInvite(
 	if err := json.Unmarshal(request.Content(), &proto); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.NotJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 
@@ -133,7 +130,7 @@ func ExchangeThirdPartyInvite(
 	if proto.RoomID != roomID {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The room ID in the request path must match the room ID in the invite event JSON"),
+			JSON: spec.BadJSON("The room ID in the request path must match the room ID in the invite event JSON"),
 		}
 	}
 
@@ -141,7 +138,7 @@ func ExchangeThirdPartyInvite(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Invalid sender ID: " + err.Error()),
+			JSON: spec.BadJSON("Invalid sender ID: " + err.Error()),
 		}
 	}
 
@@ -150,7 +147,7 @@ func ExchangeThirdPartyInvite(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event's state key isn't a Matrix user ID"),
+			JSON: spec.BadJSON("The event's state key isn't a Matrix user ID"),
 		}
 	}
 
@@ -158,7 +155,7 @@ func ExchangeThirdPartyInvite(
 	if targetDomain != request.Origin() {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The event's state key doesn't have the same domain as the request's origin"),
+			JSON: spec.BadJSON("The event's state key doesn't have the same domain as the request's origin"),
 		}
 	}
 
@@ -166,7 +163,7 @@ func ExchangeThirdPartyInvite(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.UnsupportedRoomVersion(err.Error()),
+			JSON: spec.UnsupportedRoomVersion(err.Error()),
 		}
 	}
 
@@ -175,11 +172,11 @@ func ExchangeThirdPartyInvite(
 	if err == errNotInRoom {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Unknown room " + roomID),
+			JSON: spec.NotFound("Unknown room " + roomID),
 		}
 	} else if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("buildMembershipEvent failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// Ask the requesting server to sign the newly created event so we know it
@@ -187,22 +184,22 @@ func ExchangeThirdPartyInvite(
 	inviteReq, err := fclient.NewInviteV2Request(event, nil)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("failed to make invite v2 request")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	signedEvent, err := federation.SendInviteV2(httpReq.Context(), senderDomain, request.Origin(), inviteReq)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("federation.SendInvite failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	verImpl, err := gomatrixserverlib.GetRoomVersion(roomVersion)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Errorf("unknown room version: %s", roomVersion)
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	inviteEvent, err := verImpl.NewEventFromUntrustedJSON(signedEvent.Event)
 	if err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("federation.SendInvite failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// Send the event to the roomserver
@@ -219,7 +216,7 @@ func ExchangeThirdPartyInvite(
 		false,
 	); err != nil {
 		util.GetLogger(httpReq.Context()).WithError(err).Error("SendEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/go.mod b/go.mod
index c418faa4..bd1d43fc 100644
--- a/go.mod
+++ b/go.mod
@@ -22,7 +22,7 @@ require (
 	github.com/matrix-org/dugong v0.0.0-20210921133753-66e6b1c67e2e
 	github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91
 	github.com/matrix-org/gomatrix v0.0.0-20220926102614-ceba4d9f7530
-	github.com/matrix-org/gomatrixserverlib v0.0.0-20230504085954-69034410deb1
+	github.com/matrix-org/gomatrixserverlib v0.0.0-20230509222610-6fd532036ab6
 	github.com/matrix-org/pinecone v0.11.1-0.20230210171230-8c3b24f2649a
 	github.com/matrix-org/util v0.0.0-20221111132719-399730281e66
 	github.com/mattn/go-sqlite3 v1.14.16
@@ -42,10 +42,10 @@ require (
 	github.com/uber/jaeger-lib v2.4.1+incompatible
 	github.com/yggdrasil-network/yggdrasil-go v0.4.6
 	go.uber.org/atomic v1.10.0
-	golang.org/x/crypto v0.8.0
+	golang.org/x/crypto v0.9.0
 	golang.org/x/image v0.5.0
 	golang.org/x/mobile v0.0.0-20221020085226-b36e6246172e
-	golang.org/x/term v0.7.0
+	golang.org/x/term v0.8.0
 	gopkg.in/h2non/bimg.v1 v1.1.9
 	gopkg.in/yaml.v2 v2.4.0
 	gotest.tools/v3 v3.4.0
@@ -125,8 +125,8 @@ require (
 	go.etcd.io/bbolt v1.3.6 // indirect
 	golang.org/x/exp v0.0.0-20221205204356-47842c84f3db // indirect
 	golang.org/x/mod v0.8.0 // indirect
-	golang.org/x/net v0.9.0 // indirect
-	golang.org/x/sys v0.7.0 // indirect
+	golang.org/x/net v0.10.0 // indirect
+	golang.org/x/sys v0.8.0 // indirect
 	golang.org/x/text v0.9.0 // indirect
 	golang.org/x/time v0.3.0 // indirect
 	golang.org/x/tools v0.6.0 // indirect
diff --git a/go.sum b/go.sum
index 502dcea3..733d6e24 100644
--- a/go.sum
+++ b/go.sum
@@ -323,18 +323,8 @@ github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91 h1:s7fexw
 github.com/matrix-org/go-sqlite3-js v0.0.0-20220419092513-28aa791a1c91/go.mod h1:e+cg2q7C7yE5QnAXgzo512tgFh1RbQLC0+jozuegKgo=
 github.com/matrix-org/gomatrix v0.0.0-20220926102614-ceba4d9f7530 h1:kHKxCOLcHH8r4Fzarl4+Y3K5hjothkVW5z7T1dUM11U=
 github.com/matrix-org/gomatrix v0.0.0-20220926102614-ceba4d9f7530/go.mod h1:/gBX06Kw0exX1HrwmoBibFA98yBk/jxKpGVeyQbff+s=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230428003202-267b4e79f138 h1:zqMuO/4ye8QnSPLhruxTC4cQcXfrvpPwdtT+4kqEgF4=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230428003202-267b4e79f138/go.mod h1:7HTbSZe+CIdmeqVyFMekwD5dFU8khWQyngKATvd12FU=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230428142634-a4fa967eac17 h1:So8d7SZZdKB7+vWFXwmAQ3C+tUkkegMlcGk8n60w2og=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230428142634-a4fa967eac17/go.mod h1:7HTbSZe+CIdmeqVyFMekwD5dFU8khWQyngKATvd12FU=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230502101247-782aebf83205 h1:foJFr0V1uZC0oJ3ooenScGtLViq7Hx3rioe1Hf0lnhY=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230502101247-782aebf83205/go.mod h1:7HTbSZe+CIdmeqVyFMekwD5dFU8khWQyngKATvd12FU=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230502133856-ad26780a085c h1:5xXMu/08j8tWfiVUvD4yfs6mepz07BgC4kL2i0oGJX4=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230502133856-ad26780a085c/go.mod h1:7HTbSZe+CIdmeqVyFMekwD5dFU8khWQyngKATvd12FU=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230503081352-9e29bff996eb h1:qg9iR39ctvB7A4hBcddjxmHQO/t3y4mpQnpmEc3xvNI=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230503081352-9e29bff996eb/go.mod h1:7HTbSZe+CIdmeqVyFMekwD5dFU8khWQyngKATvd12FU=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230504085954-69034410deb1 h1:K0wM4rUNdqzWVQ54am8IeQn1q6f03sTNvhUW+ZaK1Zs=
-github.com/matrix-org/gomatrixserverlib v0.0.0-20230504085954-69034410deb1/go.mod h1:7HTbSZe+CIdmeqVyFMekwD5dFU8khWQyngKATvd12FU=
+github.com/matrix-org/gomatrixserverlib v0.0.0-20230509222610-6fd532036ab6 h1:cF6fNfxC73fU9zT3pgzDXI9NDihAdnilqqGcpDWgNP4=
+github.com/matrix-org/gomatrixserverlib v0.0.0-20230509222610-6fd532036ab6/go.mod h1:7HTbSZe+CIdmeqVyFMekwD5dFU8khWQyngKATvd12FU=
 github.com/matrix-org/pinecone v0.11.1-0.20230210171230-8c3b24f2649a h1:awrPDf9LEFySxTLKYBMCiObelNx/cBuv/wzllvCCH3A=
 github.com/matrix-org/pinecone v0.11.1-0.20230210171230-8c3b24f2649a/go.mod h1:HchJX9oKMXaT2xYFs0Ha/6Zs06mxLU8k6F1ODnrGkeQ=
 github.com/matrix-org/util v0.0.0-20221111132719-399730281e66 h1:6z4KxomXSIGWqhHcfzExgkH3Z3UkIXry4ibJS4Aqz2Y=
@@ -521,8 +511,8 @@ golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20210314154223-e6e6c4f2bb5b/go.mod h1:T9bdIzuCu7OtxOm1hfPfRQxPLYneinmdGuTeoZ9dtd4=
 golang.org/x/crypto v0.0.0-20210421170649-83a5a9bb288b/go.mod h1:T9bdIzuCu7OtxOm1hfPfRQxPLYneinmdGuTeoZ9dtd4=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/crypto v0.8.0 h1:pd9TJtTueMTVQXzk8E2XESSMQDj/U7OUu0PqJqPXQjQ=
-golang.org/x/crypto v0.8.0/go.mod h1:mRqEX+O9/h5TFCrQhkgjo2yKi0yYA+9ecGkdQoHrywE=
+golang.org/x/crypto v0.9.0 h1:LF6fAI+IutBocDJ2OT0Q1g8plpYljMZ4+lty+dsqw3g=
+golang.org/x/crypto v0.9.0/go.mod h1:yrmDGqONDYtNj3tH8X9dzUun2m2lzPa9ngI6/RUPGR0=
 golang.org/x/exp v0.0.0-20180321215751-8460e604b9de/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20180807140117-3d87b88a115f/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
@@ -602,8 +592,8 @@ golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qx
 golang.org/x/net v0.0.0-20220127200216-cd36cc0744dd/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
 golang.org/x/net v0.0.0-20220225172249-27dd8689420f/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
 golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
-golang.org/x/net v0.9.0 h1:aWJ/m6xSmxWBx+V0XRHTlrYrPG56jKsLdTFmsSsCzOM=
-golang.org/x/net v0.9.0/go.mod h1:d48xBJpPfHeWQsugry2m+kC02ZBRGRgulfHnEXEuWns=
+golang.org/x/net v0.10.0 h1:X2//UzNDwYmtCLn7To6G58Wr6f5ahEAQgKNzv9Y951M=
+golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -678,12 +668,12 @@ golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20221010170243-090e33056c14/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.7.0 h1:3jlCCIQZPdOYu1h8BkNvLz8Kgwtae2cagcG/VamtZRU=
-golang.org/x/sys v0.7.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.8.0 h1:EBmGv8NaZBZTWvrbjNoL6HVt+IVy3QDQpJs7VRIw3tU=
+golang.org/x/sys v0.8.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
-golang.org/x/term v0.7.0 h1:BEvjmm5fURWqcfbSKTdpkDXYBrUS1c0m8agp14W48vQ=
-golang.org/x/term v0.7.0/go.mod h1:P32HKFT3hSsZrRxla30E9HqToFYAQPCMs/zFMBUFqPY=
+golang.org/x/term v0.8.0 h1:n5xxQn2i3PC0yLAbjTpNT85q/Kgzcr2gIoX9OrJUols=
+golang.org/x/term v0.8.0/go.mod h1:xPskH00ivmX89bAKVGSKKtLOWNx2+17Eiy94tnKShWo=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
diff --git a/internal/httputil/httpapi.go b/internal/httputil/httpapi.go
index 289d1d2c..1966e754 100644
--- a/internal/httputil/httpapi.go
+++ b/internal/httputil/httpapi.go
@@ -31,9 +31,9 @@ import (
 	"github.com/sirupsen/logrus"
 
 	"github.com/matrix-org/dendrite/clientapi/auth"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 // BasicAuth is used for authorization on /metrics handlers
@@ -101,7 +101,7 @@ func MakeAuthAPI(
 		if !opts.GuestAccessAllowed && device.AccountType == userapi.AccountTypeGuest {
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.GuestAccessForbidden("Guest access not allowed"),
+				JSON: spec.GuestAccessForbidden("Guest access not allowed"),
 			}
 		}
 
@@ -126,7 +126,7 @@ func MakeAdminAPI(
 		if device.AccountType != userapi.AccountTypeAdmin {
 			return util.JSONResponse{
 				Code: http.StatusForbidden,
-				JSON: jsonerror.Forbidden("This API can only be used by admin users."),
+				JSON: spec.Forbidden("This API can only be used by admin users."),
 			}
 		}
 		return f(req, device)
diff --git a/internal/httputil/rate_limiting.go b/internal/httputil/rate_limiting.go
index dab36481..0b040d7f 100644
--- a/internal/httputil/rate_limiting.go
+++ b/internal/httputil/rate_limiting.go
@@ -5,9 +5,9 @@ import (
 	"sync"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -118,7 +118,7 @@ func (l *RateLimits) Limit(req *http.Request, device *userapi.Device) *util.JSON
 		// We hit the rate limit. Tell the client to back off.
 		return &util.JSONResponse{
 			Code: http.StatusTooManyRequests,
-			JSON: jsonerror.LimitExceeded("You are sending too many requests too quickly!", l.cooloffDuration.Milliseconds()),
+			JSON: spec.LimitExceeded("You are sending too many requests too quickly!", l.cooloffDuration.Milliseconds()),
 		}
 	}
 
diff --git a/internal/transactionrequest.go b/internal/transactionrequest.go
index 0d250325..c9d321f2 100644
--- a/internal/transactionrequest.go
+++ b/internal/transactionrequest.go
@@ -21,7 +21,6 @@ import (
 	"sync"
 
 	"github.com/getsentry/sentry-go"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/federationapi/producers"
 	"github.com/matrix-org/dendrite/federationapi/types"
 	"github.com/matrix-org/dendrite/roomserver/api"
@@ -153,7 +152,7 @@ func (t *TxnReq) ProcessTransaction(ctx context.Context) (*fclient.RespSend, *ut
 				// See https://github.com/matrix-org/synapse/issues/7543
 				return nil, &util.JSONResponse{
 					Code: 400,
-					JSON: jsonerror.BadJSON("PDU contains bad JSON"),
+					JSON: spec.BadJSON("PDU contains bad JSON"),
 				}
 			}
 			util.GetLogger(ctx).WithError(err).Debugf("Transaction: Failed to parse event JSON of event %s", string(pdu))
diff --git a/internal/transactionrequest_test.go b/internal/transactionrequest_test.go
index c884ebfc..fb30d410 100644
--- a/internal/transactionrequest_test.go
+++ b/internal/transactionrequest_test.go
@@ -66,9 +66,8 @@ var (
 
 type FakeRsAPI struct {
 	rsAPI.RoomserverInternalAPI
-	shouldFailQuery  bool
-	bannedFromRoom   bool
-	shouldEventsFail bool
+	shouldFailQuery bool
+	bannedFromRoom  bool
 }
 
 func (r *FakeRsAPI) QueryRoomVersionForRoom(
@@ -98,11 +97,7 @@ func (r *FakeRsAPI) InputRoomEvents(
 	ctx context.Context,
 	req *rsAPI.InputRoomEventsRequest,
 	res *rsAPI.InputRoomEventsResponse,
-) error {
-	if r.shouldEventsFail {
-		return fmt.Errorf("Failure")
-	}
-	return nil
+) {
 }
 
 func TestEmptyTransactionRequest(t *testing.T) {
@@ -184,18 +179,6 @@ func TestProcessTransactionRequestPDUInvalidSignature(t *testing.T) {
 	}
 }
 
-func TestProcessTransactionRequestPDUSendFail(t *testing.T) {
-	keyRing := &test.NopJSONVerifier{}
-	txn := NewTxnReq(&FakeRsAPI{shouldEventsFail: true}, nil, "ourserver", keyRing, nil, nil, false, []json.RawMessage{testEvent}, []gomatrixserverlib.EDU{}, "", "", "")
-	txnRes, jsonRes := txn.ProcessTransaction(context.Background())
-
-	assert.Nil(t, jsonRes)
-	assert.Equal(t, 1, len(txnRes.PDUs))
-	for _, result := range txnRes.PDUs {
-		assert.NotEmpty(t, result.Error)
-	}
-}
-
 func createTransactionWithEDU(ctx *process.ProcessContext, edus []gomatrixserverlib.EDU) (TxnReq, nats.JetStreamContext, *config.Dendrite) {
 	cfg := &config.Dendrite{}
 	cfg.Defaults(config.DefaultOpts{
@@ -659,12 +642,11 @@ func (t *testRoomserverAPI) InputRoomEvents(
 	ctx context.Context,
 	request *rsAPI.InputRoomEventsRequest,
 	response *rsAPI.InputRoomEventsResponse,
-) error {
+) {
 	t.inputRoomEvents = append(t.inputRoomEvents, request.InputRoomEvents...)
 	for _, ire := range request.InputRoomEvents {
 		fmt.Println("InputRoomEvents: ", ire.Event.EventID())
 	}
-	return nil
 }
 
 // Query the latest events and state for a room from the room server.
diff --git a/internal/validate.go b/internal/validate.go
index f794d7a5..99088f24 100644
--- a/internal/validate.go
+++ b/internal/validate.go
@@ -20,7 +20,6 @@ import (
 	"net/http"
 	"regexp"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
@@ -58,12 +57,12 @@ func PasswordResponse(err error) *util.JSONResponse {
 	case ErrPasswordWeak:
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.WeakPassword(ErrPasswordWeak.Error()),
+			JSON: spec.WeakPassword(ErrPasswordWeak.Error()),
 		}
 	case ErrPasswordTooLong:
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(ErrPasswordTooLong.Error()),
+			JSON: spec.BadJSON(ErrPasswordTooLong.Error()),
 		}
 	}
 	return nil
@@ -88,12 +87,12 @@ func UsernameResponse(err error) *util.JSONResponse {
 	case ErrUsernameTooLong:
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON(err.Error()),
+			JSON: spec.BadJSON(err.Error()),
 		}
 	case ErrUsernameInvalid, ErrUsernameUnderscore:
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidUsername(err.Error()),
+			JSON: spec.InvalidUsername(err.Error()),
 		}
 	}
 	return nil
diff --git a/internal/validate_test.go b/internal/validate_test.go
index 2244b7a9..e3a10178 100644
--- a/internal/validate_test.go
+++ b/internal/validate_test.go
@@ -6,7 +6,6 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
@@ -22,13 +21,13 @@ func Test_validatePassword(t *testing.T) {
 			name:      "password too short",
 			password:  "shortpw",
 			wantError: ErrPasswordWeak,
-			wantJSON:  &util.JSONResponse{Code: http.StatusBadRequest, JSON: jsonerror.WeakPassword(ErrPasswordWeak.Error())},
+			wantJSON:  &util.JSONResponse{Code: http.StatusBadRequest, JSON: spec.WeakPassword(ErrPasswordWeak.Error())},
 		},
 		{
 			name:      "password too long",
 			password:  strings.Repeat("a", maxPasswordLength+1),
 			wantError: ErrPasswordTooLong,
-			wantJSON:  &util.JSONResponse{Code: http.StatusBadRequest, JSON: jsonerror.BadJSON(ErrPasswordTooLong.Error())},
+			wantJSON:  &util.JSONResponse{Code: http.StatusBadRequest, JSON: spec.BadJSON(ErrPasswordTooLong.Error())},
 		},
 		{
 			name:     "password OK",
@@ -65,7 +64,7 @@ func Test_validateUsername(t *testing.T) {
 			wantErr:   ErrUsernameInvalid,
 			wantJSON: &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidUsername(ErrUsernameInvalid.Error()),
+				JSON: spec.InvalidUsername(ErrUsernameInvalid.Error()),
 			},
 		},
 		{
@@ -75,7 +74,7 @@ func Test_validateUsername(t *testing.T) {
 			wantErr:   ErrUsernameInvalid,
 			wantJSON: &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidUsername(ErrUsernameInvalid.Error()),
+				JSON: spec.InvalidUsername(ErrUsernameInvalid.Error()),
 			},
 		},
 		{
@@ -85,7 +84,7 @@ func Test_validateUsername(t *testing.T) {
 			wantErr:   ErrUsernameTooLong,
 			wantJSON: &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON(ErrUsernameTooLong.Error()),
+				JSON: spec.BadJSON(ErrUsernameTooLong.Error()),
 			},
 		},
 		{
@@ -95,7 +94,7 @@ func Test_validateUsername(t *testing.T) {
 			wantErr:   ErrUsernameUnderscore,
 			wantJSON: &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidUsername(ErrUsernameUnderscore.Error()),
+				JSON: spec.InvalidUsername(ErrUsernameUnderscore.Error()),
 			},
 		},
 		{
@@ -115,7 +114,7 @@ func Test_validateUsername(t *testing.T) {
 			wantErr:   ErrUsernameInvalid,
 			wantJSON: &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidUsername(ErrUsernameInvalid.Error()),
+				JSON: spec.InvalidUsername(ErrUsernameInvalid.Error()),
 			},
 		},
 		{
@@ -135,7 +134,7 @@ func Test_validateUsername(t *testing.T) {
 			wantErr:   ErrUsernameInvalid,
 			wantJSON: &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidUsername(ErrUsernameInvalid.Error()),
+				JSON: spec.InvalidUsername(ErrUsernameInvalid.Error()),
 			},
 		},
 		{
diff --git a/mediaapi/routing/download.go b/mediaapi/routing/download.go
index bba24327..e9f161a3 100644
--- a/mediaapi/routing/download.go
+++ b/mediaapi/routing/download.go
@@ -30,7 +30,6 @@ import (
 	"sync"
 	"unicode"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/mediaapi/fileutils"
 	"github.com/matrix-org/dendrite/mediaapi/storage"
 	"github.com/matrix-org/dendrite/mediaapi/thumbnailer"
@@ -130,7 +129,7 @@ func Download(
 		// TODO: Handle the fact we might have started writing the response
 		dReq.jsonErrorResponse(w, util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("Failed to download: " + err.Error()),
+			JSON: spec.NotFound("Failed to download: " + err.Error()),
 		})
 		return
 	}
@@ -138,7 +137,7 @@ func Download(
 	if metadata == nil {
 		dReq.jsonErrorResponse(w, util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("File not found"),
+			JSON: spec.NotFound("File not found"),
 		})
 		return
 	}
@@ -168,7 +167,7 @@ func (r *downloadRequest) Validate() *util.JSONResponse {
 	if !mediaIDRegex.MatchString(string(r.MediaMetadata.MediaID)) {
 		return &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound(fmt.Sprintf("mediaId must be a non-empty string using only characters in %v", mediaIDCharacters)),
+			JSON: spec.NotFound(fmt.Sprintf("mediaId must be a non-empty string using only characters in %v", mediaIDCharacters)),
 		}
 	}
 	// Note: the origin will be validated either by comparison to the configured server name of this homeserver
@@ -176,7 +175,7 @@ func (r *downloadRequest) Validate() *util.JSONResponse {
 	if r.MediaMetadata.Origin == "" {
 		return &util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("serverName must be a non-empty string"),
+			JSON: spec.NotFound("serverName must be a non-empty string"),
 		}
 	}
 
@@ -184,7 +183,7 @@ func (r *downloadRequest) Validate() *util.JSONResponse {
 		if r.ThumbnailSize.Width <= 0 || r.ThumbnailSize.Height <= 0 {
 			return &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.Unknown("width and height must be greater than 0"),
+				JSON: spec.Unknown("width and height must be greater than 0"),
 			}
 		}
 		// Default method to scale if not set
@@ -194,7 +193,7 @@ func (r *downloadRequest) Validate() *util.JSONResponse {
 		if r.ThumbnailSize.ResizeMethod != types.Crop && r.ThumbnailSize.ResizeMethod != types.Scale {
 			return &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.Unknown("method must be one of crop or scale"),
+				JSON: spec.Unknown("method must be one of crop or scale"),
 			}
 		}
 	}
diff --git a/mediaapi/routing/upload.go b/mediaapi/routing/upload.go
index 2175648e..5061d476 100644
--- a/mediaapi/routing/upload.go
+++ b/mediaapi/routing/upload.go
@@ -26,7 +26,6 @@ import (
 	"path"
 	"strings"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/mediaapi/fileutils"
 	"github.com/matrix-org/dendrite/mediaapi/storage"
 	"github.com/matrix-org/dendrite/mediaapi/thumbnailer"
@@ -34,6 +33,7 @@ import (
 	"github.com/matrix-org/dendrite/setup/config"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 	log "github.com/sirupsen/logrus"
 )
@@ -165,7 +165,7 @@ func (r *uploadRequest) doUpload(
 		}).Warn("Error while transferring file")
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("Failed to upload"),
+			JSON: spec.Unknown("Failed to upload"),
 		}
 	}
 
@@ -184,7 +184,7 @@ func (r *uploadRequest) doUpload(
 	if err != nil {
 		fileutils.RemoveDir(tmpDir, r.Logger)
 		r.Logger.WithError(err).Error("Error querying the database by hash.")
-		resErr := jsonerror.InternalServerError()
+		resErr := spec.InternalServerError()
 		return &resErr
 	}
 	if existingMetadata != nil {
@@ -194,7 +194,7 @@ func (r *uploadRequest) doUpload(
 		mediaID, merr := r.generateMediaID(ctx, db)
 		if merr != nil {
 			r.Logger.WithError(merr).Error("Failed to generate media ID for existing file")
-			resErr := jsonerror.InternalServerError()
+			resErr := spec.InternalServerError()
 			return &resErr
 		}
 
@@ -217,7 +217,7 @@ func (r *uploadRequest) doUpload(
 		if err != nil {
 			fileutils.RemoveDir(tmpDir, r.Logger)
 			r.Logger.WithError(err).Error("Failed to generate media ID for new upload")
-			resErr := jsonerror.InternalServerError()
+			resErr := spec.InternalServerError()
 			return &resErr
 		}
 	}
@@ -239,7 +239,7 @@ func (r *uploadRequest) doUpload(
 func requestEntityTooLargeJSONResponse(maxFileSizeBytes config.FileSizeBytes) *util.JSONResponse {
 	return &util.JSONResponse{
 		Code: http.StatusRequestEntityTooLarge,
-		JSON: jsonerror.Unknown(fmt.Sprintf("HTTP Content-Length is greater than the maximum allowed upload size (%v).", maxFileSizeBytes)),
+		JSON: spec.Unknown(fmt.Sprintf("HTTP Content-Length is greater than the maximum allowed upload size (%v).", maxFileSizeBytes)),
 	}
 }
 
@@ -251,7 +251,7 @@ func (r *uploadRequest) Validate(maxFileSizeBytes config.FileSizeBytes) *util.JS
 	if strings.HasPrefix(string(r.MediaMetadata.UploadName), "~") {
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("File name must not begin with '~'."),
+			JSON: spec.Unknown("File name must not begin with '~'."),
 		}
 	}
 	// TODO: Validate filename - what are the valid characters?
@@ -264,7 +264,7 @@ func (r *uploadRequest) Validate(maxFileSizeBytes config.FileSizeBytes) *util.JS
 		if _, _, err := gomatrixserverlib.SplitID('@', string(r.MediaMetadata.UserID)); err != nil {
 			return &util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.BadJSON("user id must be in the form @localpart:domain"),
+				JSON: spec.BadJSON("user id must be in the form @localpart:domain"),
 			}
 		}
 	}
@@ -290,7 +290,7 @@ func (r *uploadRequest) storeFileAndMetadata(
 		r.Logger.WithError(err).Error("Failed to move file.")
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("Failed to upload"),
+			JSON: spec.Unknown("Failed to upload"),
 		}
 	}
 	if duplicate {
@@ -307,7 +307,7 @@ func (r *uploadRequest) storeFileAndMetadata(
 		}
 		return &util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown("Failed to upload"),
+			JSON: spec.Unknown("Failed to upload"),
 		}
 	}
 
diff --git a/relayapi/routing/relaytxn.go b/relayapi/routing/relaytxn.go
index 9a3ced52..2f3225b6 100644
--- a/relayapi/routing/relaytxn.go
+++ b/relayapi/routing/relaytxn.go
@@ -18,7 +18,6 @@ import (
 	"encoding/json"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/relayapi/api"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
 	"github.com/matrix-org/gomatrixserverlib/spec"
@@ -40,13 +39,13 @@ func GetTransactionFromRelay(
 	if err := json.Unmarshal(fedReq.Content(), &previousEntry); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.BadJSON("invalid json provided"),
+			JSON: spec.BadJSON("invalid json provided"),
 		}
 	}
 	if previousEntry.EntryID < 0 {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.BadJSON("Invalid entry id provided. Must be >= 0."),
+			JSON: spec.BadJSON("Invalid entry id provided. Must be >= 0."),
 		}
 	}
 	logrus.Infof("Previous entry provided: %v", previousEntry.EntryID)
diff --git a/relayapi/routing/routing.go b/relayapi/routing/routing.go
index 6140d032..f6e55611 100644
--- a/relayapi/routing/routing.go
+++ b/relayapi/routing/routing.go
@@ -21,7 +21,6 @@ import (
 
 	"github.com/getsentry/sentry-go"
 	"github.com/gorilla/mux"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/httputil"
 	relayInternal "github.com/matrix-org/dendrite/relayapi/internal"
 	"github.com/matrix-org/dendrite/setup/config"
@@ -59,7 +58,7 @@ func Setup(
 			if err != nil {
 				return util.JSONResponse{
 					Code: http.StatusBadRequest,
-					JSON: jsonerror.InvalidUsername("Username was invalid"),
+					JSON: spec.InvalidUsername("Username was invalid"),
 				}
 			}
 			return SendTransactionToRelay(
@@ -84,7 +83,7 @@ func Setup(
 			if err != nil {
 				return util.JSONResponse{
 					Code: http.StatusBadRequest,
-					JSON: jsonerror.InvalidUsername("Username was invalid"),
+					JSON: spec.InvalidUsername("Username was invalid"),
 				}
 			}
 			return GetTransactionFromRelay(httpReq, request, relayAPI, *userID)
diff --git a/relayapi/routing/sendrelay.go b/relayapi/routing/sendrelay.go
index 6ff08e20..4a742ded 100644
--- a/relayapi/routing/sendrelay.go
+++ b/relayapi/routing/sendrelay.go
@@ -18,7 +18,6 @@ import (
 	"encoding/json"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/relayapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
 	"github.com/matrix-org/gomatrixserverlib/fclient"
@@ -43,7 +42,7 @@ func SendTransactionToRelay(
 		logrus.Info("The request body could not be decoded into valid JSON." + err.Error())
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotJSON("The request body could not be decoded into valid JSON." + err.Error()),
+			JSON: spec.NotJSON("The request body could not be decoded into valid JSON." + err.Error()),
 		}
 	}
 
@@ -52,7 +51,7 @@ func SendTransactionToRelay(
 	if len(txnEvents.PDUs) > 50 || len(txnEvents.EDUs) > 100 {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("max 50 pdus / 100 edus"),
+			JSON: spec.BadJSON("max 50 pdus / 100 edus"),
 		}
 	}
 
@@ -69,7 +68,7 @@ func SendTransactionToRelay(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.BadJSON("could not store the transaction for forwarding"),
+			JSON: spec.BadJSON("could not store the transaction for forwarding"),
 		}
 	}
 
diff --git a/roomserver/api/api.go b/roomserver/api/api.go
index 2aaecbbf..ab1ec28f 100644
--- a/roomserver/api/api.go
+++ b/roomserver/api/api.go
@@ -60,7 +60,7 @@ type InputRoomEventsAPI interface {
 		ctx context.Context,
 		req *InputRoomEventsRequest,
 		res *InputRoomEventsResponse,
-	) error
+	)
 }
 
 // Query the latest events and state for a room from the room server.
diff --git a/roomserver/api/wrapper.go b/roomserver/api/wrapper.go
index fc26a474..2505a993 100644
--- a/roomserver/api/wrapper.go
+++ b/roomserver/api/wrapper.go
@@ -104,9 +104,7 @@ func SendInputRoomEvents(
 		VirtualHost:     virtualHost,
 	}
 	var response InputRoomEventsResponse
-	if err := rsAPI.InputRoomEvents(ctx, &request, &response); err != nil {
-		return err
-	}
+	rsAPI.InputRoomEvents(ctx, &request, &response)
 	return response.Err()
 }
 
diff --git a/roomserver/internal/input/input.go b/roomserver/internal/input/input.go
index 3e7ff7f7..3db2d0a6 100644
--- a/roomserver/internal/input/input.go
+++ b/roomserver/internal/input/input.go
@@ -389,18 +389,18 @@ func (r *Inputer) InputRoomEvents(
 	ctx context.Context,
 	request *api.InputRoomEventsRequest,
 	response *api.InputRoomEventsResponse,
-) error {
+) {
 	// Queue up the event into the roomserver.
 	replySub, err := r.queueInputRoomEvents(ctx, request)
 	if err != nil {
 		response.ErrMsg = err.Error()
-		return nil
+		return
 	}
 
 	// If we aren't waiting for synchronous responses then we can
 	// give up here, there is nothing further to do.
 	if replySub == nil {
-		return nil
+		return
 	}
 
 	// Otherwise, we'll want to sit and wait for the responses
@@ -412,14 +412,12 @@ func (r *Inputer) InputRoomEvents(
 		msg, err := replySub.NextMsgWithContext(ctx)
 		if err != nil {
 			response.ErrMsg = err.Error()
-			return nil
+			return
 		}
 		if len(msg.Data) > 0 {
 			response.ErrMsg = string(msg.Data)
 		}
 	}
-
-	return nil
 }
 
 var roomserverInputBackpressure = prometheus.NewGaugeVec(
diff --git a/roomserver/internal/input/input_events.go b/roomserver/internal/input/input_events.go
index c8f5737f..cd78b372 100644
--- a/roomserver/internal/input/input_events.go
+++ b/roomserver/internal/input/input_events.go
@@ -893,5 +893,6 @@ func (r *Inputer) kickGuests(ctx context.Context, event gomatrixserverlib.PDU, r
 		Asynchronous:    true, // Needs to be async, as we otherwise create a deadlock
 	}
 	inputRes := &api.InputRoomEventsResponse{}
-	return r.InputRoomEvents(ctx, inputReq, inputRes)
+	r.InputRoomEvents(ctx, inputReq, inputRes)
+	return nil
 }
diff --git a/roomserver/internal/perform/perform_admin.go b/roomserver/internal/perform/perform_admin.go
index 375eefbe..a539efd1 100644
--- a/roomserver/internal/perform/perform_admin.go
+++ b/roomserver/internal/perform/perform_admin.go
@@ -141,8 +141,8 @@ func (r *Admin) PerformAdminEvacuateRoom(
 		Asynchronous:    true,
 	}
 	inputRes := &api.InputRoomEventsResponse{}
-	err = r.Inputer.InputRoomEvents(ctx, inputReq, inputRes)
-	return affected, err
+	r.Inputer.InputRoomEvents(ctx, inputReq, inputRes)
+	return affected, nil
 }
 
 // PerformAdminEvacuateUser will remove the given user from all rooms.
@@ -334,9 +334,7 @@ func (r *Admin) PerformAdminDownloadState(
 		SendAsServer:  string(r.Cfg.Matrix.ServerName),
 	})
 
-	if err = r.Inputer.InputRoomEvents(ctx, inputReq, inputRes); err != nil {
-		return fmt.Errorf("r.Inputer.InputRoomEvents: %w", err)
-	}
+	r.Inputer.InputRoomEvents(ctx, inputReq, inputRes)
 
 	if inputRes.ErrMsg != "" {
 		return inputRes.Err()
diff --git a/roomserver/internal/perform/perform_invite.go b/roomserver/internal/perform/perform_invite.go
index db0b53fe..a3fa2e01 100644
--- a/roomserver/internal/perform/perform_invite.go
+++ b/roomserver/internal/perform/perform_invite.go
@@ -226,9 +226,7 @@ func (r *Inviter) PerformInvite(
 		},
 	}
 	inputRes := &api.InputRoomEventsResponse{}
-	if err = r.Inputer.InputRoomEvents(context.Background(), inputReq, inputRes); err != nil {
-		return nil, fmt.Errorf("r.Inputer.InputRoomEvents: %w", err)
-	}
+	r.Inputer.InputRoomEvents(context.Background(), inputReq, inputRes)
 	if err = inputRes.Err(); err != nil {
 		logger.WithError(err).WithField("event_id", event.EventID()).Error("r.InputRoomEvents failed")
 		return nil, api.ErrNotAllowed{Err: err}
diff --git a/roomserver/internal/perform/perform_join.go b/roomserver/internal/perform/perform_join.go
index d676bd4b..a836eb1a 100644
--- a/roomserver/internal/perform/perform_join.go
+++ b/roomserver/internal/perform/perform_join.go
@@ -313,9 +313,7 @@ func (r *Joiner) performJoinRoomByID(
 				},
 			}
 			inputRes := rsAPI.InputRoomEventsResponse{}
-			if err = r.Inputer.InputRoomEvents(ctx, &inputReq, &inputRes); err != nil {
-				return "", "", rsAPI.ErrNotAllowed{Err: err}
-			}
+			r.Inputer.InputRoomEvents(ctx, &inputReq, &inputRes)
 			if err = inputRes.Err(); err != nil {
 				return "", "", rsAPI.ErrNotAllowed{Err: err}
 			}
diff --git a/roomserver/internal/perform/perform_leave.go b/roomserver/internal/perform/perform_leave.go
index f0e95811..e71b3e90 100644
--- a/roomserver/internal/perform/perform_leave.go
+++ b/roomserver/internal/perform/perform_leave.go
@@ -21,7 +21,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/eventutil"
 	"github.com/matrix-org/gomatrix"
 	"github.com/matrix-org/gomatrixserverlib"
@@ -115,7 +114,7 @@ func (r *Leaver) performLeaveRoomByID(
 					// mimic the returned values from Synapse
 					res.Message = "You cannot reject this invite"
 					res.Code = 403
-					return nil, jsonerror.LeaveServerNoticeError()
+					return nil, spec.LeaveServerNoticeError()
 				}
 			}
 		}
@@ -203,9 +202,7 @@ func (r *Leaver) performLeaveRoomByID(
 		},
 	}
 	inputRes := api.InputRoomEventsResponse{}
-	if err = r.Inputer.InputRoomEvents(ctx, &inputReq, &inputRes); err != nil {
-		return nil, fmt.Errorf("r.Inputer.InputRoomEvents: %w", err)
-	}
+	r.Inputer.InputRoomEvents(ctx, &inputReq, &inputRes)
 	if err = inputRes.Err(); err != nil {
 		return nil, fmt.Errorf("r.InputRoomEvents: %w", err)
 	}
diff --git a/setup/mscs/msc2836/msc2836.go b/setup/mscs/msc2836/msc2836.go
index 21726c4c..e9d61fed 100644
--- a/setup/mscs/msc2836/msc2836.go
+++ b/setup/mscs/msc2836/msc2836.go
@@ -27,7 +27,6 @@ import (
 	"strings"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	fs "github.com/matrix-org/dendrite/federationapi/api"
 	"github.com/matrix-org/dendrite/internal/hooks"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -169,7 +168,7 @@ func eventRelationshipHandler(db Database, rsAPI roomserver.RoomserverInternalAP
 			util.GetLogger(req.Context()).WithError(err).Error("failed to decode HTTP request as JSON")
 			return util.JSONResponse{
 				Code: 400,
-				JSON: jsonerror.BadJSON(fmt.Sprintf("invalid json: %s", err)),
+				JSON: spec.BadJSON(fmt.Sprintf("invalid json: %s", err)),
 			}
 		}
 		rc := reqCtx{
@@ -201,7 +200,7 @@ func federatedEventRelationship(
 		util.GetLogger(ctx).WithError(err).Error("failed to decode HTTP request as JSON")
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.BadJSON(fmt.Sprintf("invalid json: %s", err)),
+			JSON: spec.BadJSON(fmt.Sprintf("invalid json: %s", err)),
 		}
 	}
 	rc := reqCtx{
@@ -268,7 +267,7 @@ func (rc *reqCtx) process() (*MSC2836EventRelationshipsResponse, *util.JSONRespo
 	if event == nil || !rc.authorisedToSeeEvent(event) {
 		return nil, &util.JSONResponse{
 			Code: 403,
-			JSON: jsonerror.Forbidden("Event does not exist or you are not authorised to see it"),
+			JSON: spec.Forbidden("Event does not exist or you are not authorised to see it"),
 		}
 	}
 	rc.roomVersion = event.Version()
@@ -428,7 +427,7 @@ func (rc *reqCtx) includeChildren(db Database, parentID string, limit int, recen
 	children, err := db.ChildrenForParent(rc.ctx, parentID, constRelType, recentFirst)
 	if err != nil {
 		util.GetLogger(rc.ctx).WithError(err).Error("failed to get ChildrenForParent")
-		resErr := jsonerror.InternalServerError()
+		resErr := spec.InternalServerError()
 		return nil, &resErr
 	}
 	var childEvents []*types.HeaderedEvent
diff --git a/setup/mscs/msc2946/msc2946.go b/setup/mscs/msc2946/msc2946.go
index b7540094..291e0f3b 100644
--- a/setup/mscs/msc2946/msc2946.go
+++ b/setup/mscs/msc2946/msc2946.go
@@ -28,7 +28,6 @@ import (
 
 	"github.com/google/uuid"
 	"github.com/gorilla/mux"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	fs "github.com/matrix-org/dendrite/federationapi/api"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -96,7 +95,7 @@ func federatedSpacesHandler(
 	if err != nil {
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.InvalidParam("bad request uri"),
+			JSON: spec.InvalidParam("bad request uri"),
 		}
 	}
 
@@ -214,13 +213,13 @@ func (w *walker) walk() util.JSONResponse {
 			// CS API format
 			return util.JSONResponse{
 				Code: 403,
-				JSON: jsonerror.Forbidden("room is unknown/forbidden"),
+				JSON: spec.Forbidden("room is unknown/forbidden"),
 			}
 		} else {
 			// SS API format
 			return util.JSONResponse{
 				Code: 404,
-				JSON: jsonerror.NotFound("room is unknown/forbidden"),
+				JSON: spec.NotFound("room is unknown/forbidden"),
 			}
 		}
 	}
@@ -233,7 +232,7 @@ func (w *walker) walk() util.JSONResponse {
 		if cache == nil {
 			return util.JSONResponse{
 				Code: 400,
-				JSON: jsonerror.InvalidArgumentValue("invalid from"),
+				JSON: spec.InvalidParam("invalid from"),
 			}
 		}
 	} else {
@@ -377,7 +376,7 @@ func (w *walker) walk() util.JSONResponse {
 	if len(discoveredRooms) == 0 {
 		return util.JSONResponse{
 			Code: 404,
-			JSON: jsonerror.NotFound("room is unknown/forbidden"),
+			JSON: spec.NotFound("room is unknown/forbidden"),
 		}
 	}
 	return util.JSONResponse{
diff --git a/syncapi/internal/keychange_test.go b/syncapi/internal/keychange_test.go
index 11954904..23c2ecba 100644
--- a/syncapi/internal/keychange_test.go
+++ b/syncapi/internal/keychange_test.go
@@ -34,20 +34,16 @@ func (k *mockKeyAPI) PerformUploadKeys(ctx context.Context, req *userapi.Perform
 func (k *mockKeyAPI) SetUserAPI(i userapi.UserInternalAPI) {}
 
 // PerformClaimKeys claims one-time keys for use in pre-key messages
-func (k *mockKeyAPI) PerformClaimKeys(ctx context.Context, req *userapi.PerformClaimKeysRequest, res *userapi.PerformClaimKeysResponse) error {
-	return nil
+func (k *mockKeyAPI) PerformClaimKeys(ctx context.Context, req *userapi.PerformClaimKeysRequest, res *userapi.PerformClaimKeysResponse) {
 }
 func (k *mockKeyAPI) PerformDeleteKeys(ctx context.Context, req *userapi.PerformDeleteKeysRequest, res *userapi.PerformDeleteKeysResponse) error {
 	return nil
 }
-func (k *mockKeyAPI) PerformUploadDeviceKeys(ctx context.Context, req *userapi.PerformUploadDeviceKeysRequest, res *userapi.PerformUploadDeviceKeysResponse) error {
-	return nil
+func (k *mockKeyAPI) PerformUploadDeviceKeys(ctx context.Context, req *userapi.PerformUploadDeviceKeysRequest, res *userapi.PerformUploadDeviceKeysResponse) {
 }
-func (k *mockKeyAPI) PerformUploadDeviceSignatures(ctx context.Context, req *userapi.PerformUploadDeviceSignaturesRequest, res *userapi.PerformUploadDeviceSignaturesResponse) error {
-	return nil
+func (k *mockKeyAPI) PerformUploadDeviceSignatures(ctx context.Context, req *userapi.PerformUploadDeviceSignaturesRequest, res *userapi.PerformUploadDeviceSignaturesResponse) {
 }
-func (k *mockKeyAPI) QueryKeys(ctx context.Context, req *userapi.QueryKeysRequest, res *userapi.QueryKeysResponse) error {
-	return nil
+func (k *mockKeyAPI) QueryKeys(ctx context.Context, req *userapi.QueryKeysRequest, res *userapi.QueryKeysResponse) {
 }
 func (k *mockKeyAPI) QueryKeyChanges(ctx context.Context, req *userapi.QueryKeyChangesRequest, res *userapi.QueryKeyChangesResponse) error {
 	return nil
@@ -60,8 +56,7 @@ func (k *mockKeyAPI) QueryDeviceMessages(ctx context.Context, req *userapi.Query
 	return nil
 
 }
-func (k *mockKeyAPI) QuerySignatures(ctx context.Context, req *userapi.QuerySignaturesRequest, res *userapi.QuerySignaturesResponse) error {
-	return nil
+func (k *mockKeyAPI) QuerySignatures(ctx context.Context, req *userapi.QuerySignaturesRequest, res *userapi.QuerySignaturesResponse) {
 }
 
 type mockRoomserverAPI struct {
diff --git a/syncapi/routing/context.go b/syncapi/routing/context.go
index b85ab7f2..8ff656e7 100644
--- a/syncapi/routing/context.go
+++ b/syncapi/routing/context.go
@@ -23,7 +23,6 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	roomserver "github.com/matrix-org/dendrite/roomserver/api"
@@ -57,7 +56,7 @@ func Context(
 ) util.JSONResponse {
 	snapshot, err := syncDB.NewDatabaseSnapshot(req.Context())
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	var succeeded bool
 	defer sqlutil.EndTransactionWithCheck(snapshot, &succeeded, &err)
@@ -75,7 +74,7 @@ func Context(
 		}
 		return util.JSONResponse{
 			Code:    http.StatusBadRequest,
-			JSON:    jsonerror.InvalidParam(errMsg),
+			JSON:    spec.InvalidParam(errMsg),
 			Headers: nil,
 		}
 	}
@@ -88,12 +87,12 @@ func Context(
 	membershipReq := roomserver.QueryMembershipForUserRequest{UserID: device.UserID, RoomID: roomID}
 	if err = rsAPI.QueryMembershipForUser(ctx, &membershipReq, &membershipRes); err != nil {
 		logrus.WithError(err).Error("unable to query membership")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !membershipRes.RoomExists {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("room does not exist"),
+			JSON: spec.Forbidden("room does not exist"),
 		}
 	}
 
@@ -114,11 +113,11 @@ func Context(
 		if err == sql.ErrNoRows {
 			return util.JSONResponse{
 				Code: http.StatusNotFound,
-				JSON: jsonerror.NotFound(fmt.Sprintf("Event %s not found", eventID)),
+				JSON: spec.NotFound(fmt.Sprintf("Event %s not found", eventID)),
 			}
 		}
 		logrus.WithError(err).WithField("eventID", eventID).Error("unable to find requested event")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// verify the user is allowed to see the context for this room/event
@@ -126,7 +125,7 @@ func Context(
 	filteredEvents, err := internal.ApplyHistoryVisibilityFilter(ctx, snapshot, rsAPI, []*rstypes.HeaderedEvent{&requestedEvent}, nil, device.UserID, "context")
 	if err != nil {
 		logrus.WithError(err).Error("unable to apply history visibility filter")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	logrus.WithFields(logrus.Fields{
 		"duration": time.Since(startTime),
@@ -135,27 +134,27 @@ func Context(
 	if len(filteredEvents) == 0 {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("User is not allowed to query context"),
+			JSON: spec.Forbidden("User is not allowed to query context"),
 		}
 	}
 
 	eventsBefore, err := snapshot.SelectContextBeforeEvent(ctx, id, roomID, filter)
 	if err != nil && err != sql.ErrNoRows {
 		logrus.WithError(err).Error("unable to fetch before events")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	_, eventsAfter, err := snapshot.SelectContextAfterEvent(ctx, id, roomID, filter)
 	if err != nil && err != sql.ErrNoRows {
 		logrus.WithError(err).Error("unable to fetch after events")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	startTime = time.Now()
 	eventsBeforeFiltered, eventsAfterFiltered, err := applyHistoryVisibilityOnContextEvents(ctx, snapshot, rsAPI, eventsBefore, eventsAfter, device.UserID)
 	if err != nil {
 		logrus.WithError(err).Error("unable to apply history visibility filter")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	logrus.WithFields(logrus.Fields{
@@ -167,7 +166,7 @@ func Context(
 	state, err := snapshot.CurrentState(ctx, roomID, &stateFilter, nil)
 	if err != nil {
 		logrus.WithError(err).Error("unable to fetch current room state")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	eventsBeforeClient := synctypes.ToClientEvents(gomatrixserverlib.ToPDUs(eventsBeforeFiltered), synctypes.FormatAll)
@@ -181,7 +180,7 @@ func Context(
 		newState, err = applyLazyLoadMembers(ctx, device, snapshot, roomID, evs, lazyLoadCache)
 		if err != nil {
 			logrus.WithError(err).Error("unable to load membership events")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
diff --git a/syncapi/routing/filter.go b/syncapi/routing/filter.go
index 266ad4ad..5152e1f8 100644
--- a/syncapi/routing/filter.go
+++ b/syncapi/routing/filter.go
@@ -23,11 +23,11 @@ import (
 	"github.com/matrix-org/util"
 	"github.com/tidwall/gjson"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/syncapi/storage"
 	"github.com/matrix-org/dendrite/syncapi/sync"
 	"github.com/matrix-org/dendrite/syncapi/synctypes"
 	"github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 // GetFilter implements GET /_matrix/client/r0/user/{userId}/filter/{filterId}
@@ -37,13 +37,13 @@ func GetFilter(
 	if userID != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Cannot get filters for other users"),
+			JSON: spec.Forbidden("Cannot get filters for other users"),
 		}
 	}
 	localpart, _, err := gomatrixserverlib.SplitID('@', userID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	filter := synctypes.DefaultFilter()
@@ -53,7 +53,7 @@ func GetFilter(
 		// even though it is not correct.
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.NotFound("No such filter"),
+			JSON: spec.NotFound("No such filter"),
 		}
 	}
 
@@ -76,14 +76,14 @@ func PutFilter(
 	if userID != device.UserID {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("Cannot create filters for other users"),
+			JSON: spec.Forbidden("Cannot create filters for other users"),
 		}
 	}
 
 	localpart, _, err := gomatrixserverlib.SplitID('@', userID)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("gomatrixserverlib.SplitID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	var filter synctypes.Filter
@@ -93,14 +93,14 @@ func PutFilter(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be read. " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be read. " + err.Error()),
 		}
 	}
 
 	if err = json.Unmarshal(body, &filter); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
+			JSON: spec.BadJSON("The request body could not be decoded into valid JSON. " + err.Error()),
 		}
 	}
 	// the filter `limit` is `int` which defaults to 0 if not set which is not what we want. We want to use the default
@@ -115,14 +115,14 @@ func PutFilter(
 	if err = filter.Validate(); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.BadJSON("Invalid filter: " + err.Error()),
+			JSON: spec.BadJSON("Invalid filter: " + err.Error()),
 		}
 	}
 
 	filterID, err := syncDB.PutFilter(req.Context(), localpart, &filter)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("syncDB.PutFilter failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	return util.JSONResponse{
diff --git a/syncapi/routing/getevent.go b/syncapi/routing/getevent.go
index 7775598e..e3d77cc3 100644
--- a/syncapi/routing/getevent.go
+++ b/syncapi/routing/getevent.go
@@ -20,13 +20,13 @@ import (
 	"github.com/matrix-org/util"
 	"github.com/sirupsen/logrus"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
 	"github.com/matrix-org/dendrite/syncapi/internal"
 	"github.com/matrix-org/dendrite/syncapi/storage"
 	"github.com/matrix-org/dendrite/syncapi/synctypes"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 // GetEvent implements
@@ -51,13 +51,13 @@ func GetEvent(
 	})
 	if err != nil {
 		logger.WithError(err).Error("GetEvent: syncDB.NewDatabaseTransaction failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	events, err := db.Events(ctx, []string{eventID})
 	if err != nil {
 		logger.WithError(err).Error("GetEvent: syncDB.Events failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	// The requested event does not exist in our database
@@ -65,7 +65,7 @@ func GetEvent(
 		logger.Debugf("GetEvent: requested event doesn't exist locally")
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("The event was not found or you do not have permission to read this event"),
+			JSON: spec.NotFound("The event was not found or you do not have permission to read this event"),
 		}
 	}
 
@@ -81,7 +81,7 @@ func GetEvent(
 		logger.WithError(err).Error("GetEvent: internal.ApplyHistoryVisibilityFilter failed")
 		return util.JSONResponse{
 			Code: http.StatusInternalServerError,
-			JSON: jsonerror.InternalServerError(),
+			JSON: spec.InternalServerError(),
 		}
 	}
 
@@ -91,7 +91,7 @@ func GetEvent(
 		logger.WithField("event_count", len(events)).Debug("GetEvent: can't return the requested event")
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("The event was not found or you do not have permission to read this event"),
+			JSON: spec.NotFound("The event was not found or you do not have permission to read this event"),
 		}
 	}
 
diff --git a/syncapi/routing/memberships.go b/syncapi/routing/memberships.go
index a23f1525..5a66009c 100644
--- a/syncapi/routing/memberships.go
+++ b/syncapi/routing/memberships.go
@@ -19,13 +19,13 @@ import (
 	"math"
 	"net/http"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/syncapi/storage"
 	"github.com/matrix-org/dendrite/syncapi/synctypes"
 	"github.com/matrix-org/dendrite/syncapi/types"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 )
 
@@ -67,26 +67,26 @@ func GetMemberships(
 	var queryRes api.QueryMembershipForUserResponse
 	if err := rsAPI.QueryMembershipForUser(req.Context(), &queryReq, &queryRes); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("rsAPI.QueryMembershipsForRoom failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	if !queryRes.HasBeenInRoom {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You aren't a member of the room and weren't previously a member of the room."),
+			JSON: spec.Forbidden("You aren't a member of the room and weren't previously a member of the room."),
 		}
 	}
 
 	if joinedOnly && !queryRes.IsInRoom {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("You aren't a member of the room and weren't previously a member of the room."),
+			JSON: spec.Forbidden("You aren't a member of the room and weren't previously a member of the room."),
 		}
 	}
 
 	db, err := syncDB.NewDatabaseSnapshot(req.Context())
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	defer db.Rollback() // nolint: errcheck
 
@@ -98,7 +98,7 @@ func GetMemberships(
 			atToken, err = db.EventPositionInTopology(req.Context(), queryRes.EventID)
 			if err != nil {
 				util.GetLogger(req.Context()).WithError(err).Error("unable to get 'atToken'")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 		}
 	}
@@ -106,13 +106,13 @@ func GetMemberships(
 	eventIDs, err := db.SelectMemberships(req.Context(), roomID, atToken, membership, notMembership)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("db.SelectMemberships failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	qryRes := &api.QueryEventsByIDResponse{}
 	if err := rsAPI.QueryEventsByID(req.Context(), &api.QueryEventsByIDRequest{EventIDs: eventIDs, RoomID: roomID}, qryRes); err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("rsAPI.QueryEventsByID failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	result := qryRes.Events
@@ -124,7 +124,7 @@ func GetMemberships(
 			var content databaseJoinedMember
 			if err := json.Unmarshal(ev.Content(), &content); err != nil {
 				util.GetLogger(req.Context()).WithError(err).Error("failed to unmarshal event content")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 			res.Joined[ev.Sender()] = joinedMember(content)
 		}
diff --git a/syncapi/routing/messages.go b/syncapi/routing/messages.go
index 54b72c64..4d3c9e2e 100644
--- a/syncapi/routing/messages.go
+++ b/syncapi/routing/messages.go
@@ -27,7 +27,6 @@ import (
 	"github.com/matrix-org/util"
 	"github.com/sirupsen/logrus"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/roomserver/api"
@@ -82,7 +81,7 @@ func OnIncomingMessagesRequest(
 	// request that requires backfilling from the roomserver or federation.
 	snapshot, err := db.NewDatabaseTransaction(req.Context())
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	var succeeded bool
 	defer sqlutil.EndTransactionWithCheck(snapshot, &succeeded, &err)
@@ -90,19 +89,19 @@ func OnIncomingMessagesRequest(
 	// check if the user has already forgotten about this room
 	membershipResp, err := getMembershipForUser(req.Context(), roomID, device.UserID, rsAPI)
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if !membershipResp.RoomExists {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("room does not exist"),
+			JSON: spec.Forbidden("room does not exist"),
 		}
 	}
 
 	if membershipResp.IsRoomForgotten {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Forbidden("user already forgot about this room"),
+			JSON: spec.Forbidden("user already forgot about this room"),
 		}
 	}
 
@@ -110,7 +109,7 @@ func OnIncomingMessagesRequest(
 	if err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.InvalidArgumentValue("unable to parse filter"),
+			JSON: spec.InvalidParam("unable to parse filter"),
 		}
 	}
 
@@ -132,7 +131,7 @@ func OnIncomingMessagesRequest(
 	if dir != "b" && dir != "f" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Bad or missing dir query parameter (should be either 'b' or 'f')"),
+			JSON: spec.MissingParam("Bad or missing dir query parameter (should be either 'b' or 'f')"),
 		}
 	}
 	// A boolean is easier to handle in this case, especially since dir is sure
@@ -145,14 +144,14 @@ func OnIncomingMessagesRequest(
 		if streamToken, err = types.NewStreamTokenFromString(fromQuery); err != nil {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue("Invalid from parameter: " + err.Error()),
+				JSON: spec.InvalidParam("Invalid from parameter: " + err.Error()),
 			}
 		} else {
 			fromStream = &streamToken
 			from, err = snapshot.StreamToTopologicalPosition(req.Context(), roomID, streamToken.PDUPosition, backwardOrdering)
 			if err != nil {
 				logrus.WithError(err).Errorf("Failed to get topological position for streaming token %v", streamToken)
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 		}
 	}
@@ -168,13 +167,13 @@ func OnIncomingMessagesRequest(
 			if streamToken, err = types.NewStreamTokenFromString(toQuery); err != nil {
 				return util.JSONResponse{
 					Code: http.StatusBadRequest,
-					JSON: jsonerror.InvalidArgumentValue("Invalid to parameter: " + err.Error()),
+					JSON: spec.InvalidParam("Invalid to parameter: " + err.Error()),
 				}
 			} else {
 				to, err = snapshot.StreamToTopologicalPosition(req.Context(), roomID, streamToken.PDUPosition, !backwardOrdering)
 				if err != nil {
 					logrus.WithError(err).Errorf("Failed to get topological position for streaming token %v", streamToken)
-					return jsonerror.InternalServerError()
+					return spec.InternalServerError()
 				}
 			}
 		}
@@ -197,7 +196,7 @@ func OnIncomingMessagesRequest(
 	if _, _, err = gomatrixserverlib.SplitID('!', roomID); err != nil {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Bad room ID: " + err.Error()),
+			JSON: spec.MissingParam("Bad room ID: " + err.Error()),
 		}
 	}
 
@@ -233,7 +232,7 @@ func OnIncomingMessagesRequest(
 	clientEvents, start, end, err := mReq.retrieveEvents()
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("mreq.retrieveEvents failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	util.GetLogger(req.Context()).WithFields(logrus.Fields{
@@ -254,7 +253,7 @@ func OnIncomingMessagesRequest(
 		membershipEvents, err := applyLazyLoadMembers(req.Context(), device, snapshot, roomID, clientEvents, lazyLoadCache)
 		if err != nil {
 			util.GetLogger(req.Context()).WithError(err).Error("failed to apply lazy loading")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		res.State = append(res.State, synctypes.ToClientEvents(gomatrixserverlib.ToPDUs(membershipEvents), synctypes.FormatAll)...)
 	}
diff --git a/syncapi/routing/relations.go b/syncapi/routing/relations.go
index 55e4347d..2bf11a56 100644
--- a/syncapi/routing/relations.go
+++ b/syncapi/routing/relations.go
@@ -21,7 +21,6 @@ import (
 	"github.com/matrix-org/util"
 	"github.com/sirupsen/logrus"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/roomserver/api"
 	rstypes "github.com/matrix-org/dendrite/roomserver/types"
@@ -30,6 +29,7 @@ import (
 	"github.com/matrix-org/dendrite/syncapi/synctypes"
 	"github.com/matrix-org/dendrite/syncapi/types"
 	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
 )
 
 type RelationsResponse struct {
@@ -73,14 +73,14 @@ func Relations(
 	if dir != "b" && dir != "f" {
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.MissingArgument("Bad or missing dir query parameter (should be either 'b' or 'f')"),
+			JSON: spec.MissingParam("Bad or missing dir query parameter (should be either 'b' or 'f')"),
 		}
 	}
 
 	snapshot, err := syncDB.NewDatabaseSnapshot(req.Context())
 	if err != nil {
 		logrus.WithError(err).Error("Failed to get snapshot for relations")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	var succeeded bool
 	defer sqlutil.EndTransactionWithCheck(snapshot, &succeeded, &err)
diff --git a/syncapi/routing/routing.go b/syncapi/routing/routing.go
index 9607aa32..88c5c504 100644
--- a/syncapi/routing/routing.go
+++ b/syncapi/routing/routing.go
@@ -21,7 +21,6 @@ import (
 	"github.com/matrix-org/gomatrixserverlib/spec"
 	"github.com/matrix-org/util"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/caching"
 	"github.com/matrix-org/dendrite/internal/fulltext"
 	"github.com/matrix-org/dendrite/internal/httputil"
@@ -158,12 +157,12 @@ func Setup(
 			if !cfg.Fulltext.Enabled {
 				return util.JSONResponse{
 					Code: http.StatusNotImplemented,
-					JSON: jsonerror.Unknown("Search has been disabled by the server administrator."),
+					JSON: spec.Unknown("Search has been disabled by the server administrator."),
 				}
 			}
 			var nextBatch *string
 			if err := req.ParseForm(); err != nil {
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 			if req.Form.Has("next_batch") {
 				nb := req.FormValue("next_batch")
diff --git a/syncapi/routing/search.go b/syncapi/routing/search.go
index 5f037392..986284d0 100644
--- a/syncapi/routing/search.go
+++ b/syncapi/routing/search.go
@@ -29,7 +29,6 @@ import (
 	"github.com/tidwall/gjson"
 
 	"github.com/matrix-org/dendrite/clientapi/httputil"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/fulltext"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	"github.com/matrix-org/dendrite/roomserver/types"
@@ -56,7 +55,7 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 	if from != nil && *from != "" {
 		nextBatch, err = strconv.Atoi(*from)
 		if err != nil {
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 	}
 
@@ -66,7 +65,7 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 
 	snapshot, err := syncDB.NewDatabaseSnapshot(req.Context())
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	var succeeded bool
 	defer sqlutil.EndTransactionWithCheck(snapshot, &succeeded, &err)
@@ -74,12 +73,12 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 	// only search rooms the user is actually joined to
 	joinedRooms, err := snapshot.RoomIDsWithMembership(ctx, device.UserID, "join")
 	if err != nil {
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	if len(joinedRooms) == 0 {
 		return util.JSONResponse{
 			Code: http.StatusNotFound,
-			JSON: jsonerror.NotFound("User not joined to any rooms."),
+			JSON: spec.NotFound("User not joined to any rooms."),
 		}
 	}
 	joinedRoomsMap := make(map[string]struct{}, len(joinedRooms))
@@ -100,7 +99,7 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 	if len(rooms) == 0 {
 		return util.JSONResponse{
 			Code: http.StatusForbidden,
-			JSON: jsonerror.Unknown("User not allowed to search in this room(s)."),
+			JSON: spec.Unknown("User not allowed to search in this room(s)."),
 		}
 	}
 
@@ -116,7 +115,7 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 	)
 	if err != nil {
 		logrus.WithError(err).Error("failed to search fulltext")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	logrus.Debugf("Search took %s", result.Took)
 
@@ -156,7 +155,7 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 	evs, err := syncDB.Events(ctx, wantEvents)
 	if err != nil {
 		logrus.WithError(err).Error("failed to get events from database")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 
 	groups := make(map[string]RoomResult)
@@ -174,12 +173,12 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 		eventsBefore, eventsAfter, err := contextEvents(ctx, snapshot, event, roomFilter, searchReq)
 		if err != nil {
 			logrus.WithError(err).Error("failed to get context events")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 		startToken, endToken, err := getStartEnd(ctx, snapshot, eventsBefore, eventsAfter)
 		if err != nil {
 			logrus.WithError(err).Error("failed to get start/end")
-			return jsonerror.InternalServerError()
+			return spec.InternalServerError()
 		}
 
 		profileInfos := make(map[string]ProfileInfoResponse)
@@ -222,7 +221,7 @@ func Search(req *http.Request, device *api.Device, syncDB storage.Database, fts
 			state, err := snapshot.CurrentState(ctx, event.RoomID(), &stateFilter, nil)
 			if err != nil {
 				logrus.WithError(err).Error("unable to get current state")
-				return jsonerror.InternalServerError()
+				return spec.InternalServerError()
 			}
 			stateForRooms[event.RoomID()] = synctypes.ToClientEvents(gomatrixserverlib.ToPDUs(state), synctypes.FormatSync)
 		}
diff --git a/syncapi/sync/requestpool.go b/syncapi/sync/requestpool.go
index 6baaff3c..09e5dee1 100644
--- a/syncapi/sync/requestpool.go
+++ b/syncapi/sync/requestpool.go
@@ -30,7 +30,6 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/sirupsen/logrus"
 
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	"github.com/matrix-org/dendrite/internal/sqlutil"
 	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
 	"github.com/matrix-org/dendrite/setup/config"
@@ -232,12 +231,12 @@ func (rp *RequestPool) OnIncomingSyncRequest(req *http.Request, device *userapi.
 		if err == types.ErrMalformedSyncToken {
 			return util.JSONResponse{
 				Code: http.StatusBadRequest,
-				JSON: jsonerror.InvalidArgumentValue(err.Error()),
+				JSON: spec.InvalidParam(err.Error()),
 			}
 		}
 		return util.JSONResponse{
 			Code: http.StatusBadRequest,
-			JSON: jsonerror.Unknown(err.Error()),
+			JSON: spec.Unknown(err.Error()),
 		}
 	}
 
@@ -517,32 +516,32 @@ func (rp *RequestPool) OnIncomingKeyChangeRequest(req *http.Request, device *use
 	if from == "" || to == "" {
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.InvalidArgumentValue("missing ?from= or ?to="),
+			JSON: spec.InvalidParam("missing ?from= or ?to="),
 		}
 	}
 	fromToken, err := types.NewStreamTokenFromString(from)
 	if err != nil {
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.InvalidArgumentValue("bad 'from' value"),
+			JSON: spec.InvalidParam("bad 'from' value"),
 		}
 	}
 	toToken, err := types.NewStreamTokenFromString(to)
 	if err != nil {
 		return util.JSONResponse{
 			Code: 400,
-			JSON: jsonerror.InvalidArgumentValue("bad 'to' value"),
+			JSON: spec.InvalidParam("bad 'to' value"),
 		}
 	}
 	syncReq, err := newSyncRequest(req, *device, rp.db)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("newSyncRequest failed")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	snapshot, err := rp.db.NewDatabaseSnapshot(req.Context())
 	if err != nil {
 		logrus.WithError(err).Error("Failed to acquire database snapshot for key change")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	var succeeded bool
 	defer sqlutil.EndTransactionWithCheck(snapshot, &succeeded, &err)
@@ -553,7 +552,7 @@ func (rp *RequestPool) OnIncomingKeyChangeRequest(req *http.Request, device *use
 	)
 	if err != nil {
 		util.GetLogger(req.Context()).WithError(err).Error("Failed to DeviceListCatchup info")
-		return jsonerror.InternalServerError()
+		return spec.InternalServerError()
 	}
 	succeeded = true
 	return util.JSONResponse{
diff --git a/userapi/api/api.go b/userapi/api/api.go
index 4e13a3b9..05040264 100644
--- a/userapi/api/api.go
+++ b/userapi/api/api.go
@@ -63,10 +63,10 @@ type FederationUserAPI interface {
 	QueryOpenIDToken(ctx context.Context, req *QueryOpenIDTokenRequest, res *QueryOpenIDTokenResponse) error
 	QueryProfile(ctx context.Context, userID string) (*authtypes.Profile, error)
 	QueryDevices(ctx context.Context, req *QueryDevicesRequest, res *QueryDevicesResponse) error
-	QueryKeys(ctx context.Context, req *QueryKeysRequest, res *QueryKeysResponse) error
-	QuerySignatures(ctx context.Context, req *QuerySignaturesRequest, res *QuerySignaturesResponse) error
+	QueryKeys(ctx context.Context, req *QueryKeysRequest, res *QueryKeysResponse)
+	QuerySignatures(ctx context.Context, req *QuerySignaturesRequest, res *QuerySignaturesResponse)
 	QueryDeviceMessages(ctx context.Context, req *QueryDeviceMessagesRequest, res *QueryDeviceMessagesResponse) error
-	PerformClaimKeys(ctx context.Context, req *PerformClaimKeysRequest, res *PerformClaimKeysResponse) error
+	PerformClaimKeys(ctx context.Context, req *PerformClaimKeysRequest, res *PerformClaimKeysResponse)
 }
 
 // api functions required by the sync api
@@ -646,17 +646,17 @@ type QueryAccountByLocalpartResponse struct {
 // API functions required by the clientapi
 type ClientKeyAPI interface {
 	UploadDeviceKeysAPI
-	QueryKeys(ctx context.Context, req *QueryKeysRequest, res *QueryKeysResponse) error
+	QueryKeys(ctx context.Context, req *QueryKeysRequest, res *QueryKeysResponse)
 	PerformUploadKeys(ctx context.Context, req *PerformUploadKeysRequest, res *PerformUploadKeysResponse) error
 
-	PerformUploadDeviceSignatures(ctx context.Context, req *PerformUploadDeviceSignaturesRequest, res *PerformUploadDeviceSignaturesResponse) error
+	PerformUploadDeviceSignatures(ctx context.Context, req *PerformUploadDeviceSignaturesRequest, res *PerformUploadDeviceSignaturesResponse)
 	// PerformClaimKeys claims one-time keys for use in pre-key messages
-	PerformClaimKeys(ctx context.Context, req *PerformClaimKeysRequest, res *PerformClaimKeysResponse) error
+	PerformClaimKeys(ctx context.Context, req *PerformClaimKeysRequest, res *PerformClaimKeysResponse)
 	PerformMarkAsStaleIfNeeded(ctx context.Context, req *PerformMarkAsStaleRequest, res *struct{}) error
 }
 
 type UploadDeviceKeysAPI interface {
-	PerformUploadDeviceKeys(ctx context.Context, req *PerformUploadDeviceKeysRequest, res *PerformUploadDeviceKeysResponse) error
+	PerformUploadDeviceKeys(ctx context.Context, req *PerformUploadDeviceKeysRequest, res *PerformUploadDeviceKeysResponse)
 }
 
 // API functions required by the syncapi
@@ -668,10 +668,10 @@ type SyncKeyAPI interface {
 
 type FederationKeyAPI interface {
 	UploadDeviceKeysAPI
-	QueryKeys(ctx context.Context, req *QueryKeysRequest, res *QueryKeysResponse) error
-	QuerySignatures(ctx context.Context, req *QuerySignaturesRequest, res *QuerySignaturesResponse) error
+	QueryKeys(ctx context.Context, req *QueryKeysRequest, res *QueryKeysResponse)
+	QuerySignatures(ctx context.Context, req *QuerySignaturesRequest, res *QuerySignaturesResponse)
 	QueryDeviceMessages(ctx context.Context, req *QueryDeviceMessagesRequest, res *QueryDeviceMessagesResponse) error
-	PerformClaimKeys(ctx context.Context, req *PerformClaimKeysRequest, res *PerformClaimKeysResponse) error
+	PerformClaimKeys(ctx context.Context, req *PerformClaimKeysRequest, res *PerformClaimKeysResponse)
 }
 
 // KeyError is returned if there was a problem performing/querying the server
diff --git a/userapi/consumers/signingkeyupdate.go b/userapi/consumers/signingkeyupdate.go
index 457a6183..9de86634 100644
--- a/userapi/consumers/signingkeyupdate.go
+++ b/userapi/consumers/signingkeyupdate.go
@@ -100,10 +100,7 @@ func (t *SigningKeyUpdateConsumer) onMessage(ctx context.Context, msgs []*nats.M
 		UserID:           updatePayload.UserID,
 	}
 	uploadRes := &api.PerformUploadDeviceKeysResponse{}
-	if err := t.userAPI.PerformUploadDeviceKeys(ctx, uploadReq, uploadRes); err != nil {
-		logrus.WithError(err).Error("failed to upload device keys")
-		return false
-	}
+	t.userAPI.PerformUploadDeviceKeys(ctx, uploadReq, uploadRes)
 	if uploadRes.Error != nil {
 		logrus.WithError(uploadRes.Error).Error("failed to upload device keys")
 		return true
diff --git a/userapi/internal/cross_signing.go b/userapi/internal/cross_signing.go
index ea7b84f6..be05841c 100644
--- a/userapi/internal/cross_signing.go
+++ b/userapi/internal/cross_signing.go
@@ -105,7 +105,7 @@ func sanityCheckKey(key fclient.CrossSigningKey, userID string, purpose fclient.
 }
 
 // nolint:gocyclo
-func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.PerformUploadDeviceKeysRequest, res *api.PerformUploadDeviceKeysResponse) error {
+func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.PerformUploadDeviceKeysRequest, res *api.PerformUploadDeviceKeysResponse) {
 	// Find the keys to store.
 	byPurpose := map[fclient.CrossSigningKeyPurpose]fclient.CrossSigningKey{}
 	toStore := types.CrossSigningKeyMap{}
@@ -117,7 +117,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 				Err:            "Master key sanity check failed: " + err.Error(),
 				IsInvalidParam: true,
 			}
-			return nil
+			return
 		}
 
 		byPurpose[fclient.CrossSigningKeyPurposeMaster] = req.MasterKey
@@ -133,7 +133,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 				Err:            "Self-signing key sanity check failed: " + err.Error(),
 				IsInvalidParam: true,
 			}
-			return nil
+			return
 		}
 
 		byPurpose[fclient.CrossSigningKeyPurposeSelfSigning] = req.SelfSigningKey
@@ -148,7 +148,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 				Err:            "User-signing key sanity check failed: " + err.Error(),
 				IsInvalidParam: true,
 			}
-			return nil
+			return
 		}
 
 		byPurpose[fclient.CrossSigningKeyPurposeUserSigning] = req.UserSigningKey
@@ -163,7 +163,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 			Err:            "No keys were supplied in the request",
 			IsMissingParam: true,
 		}
-		return nil
+		return
 	}
 
 	// We can't have a self-signing or user-signing key without a master
@@ -176,7 +176,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 		res.Error = &api.KeyError{
 			Err: "Retrieving cross-signing keys from database failed: " + err.Error(),
 		}
-		return nil
+		return
 	}
 
 	// If we still can't find a master key for the user then stop the upload.
@@ -187,7 +187,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 				Err:            "No master key was found",
 				IsMissingParam: true,
 			}
-			return nil
+			return
 		}
 	}
 
@@ -214,7 +214,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 		}
 	}
 	if !changed {
-		return nil
+		return
 	}
 
 	// Store the keys.
@@ -222,7 +222,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 		res.Error = &api.KeyError{
 			Err: fmt.Sprintf("a.DB.StoreCrossSigningKeysForUser: %s", err),
 		}
-		return nil
+		return
 	}
 
 	// Now upload any signatures that were included with the keys.
@@ -240,7 +240,7 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 					res.Error = &api.KeyError{
 						Err: fmt.Sprintf("a.DB.StoreCrossSigningSigsForTarget: %s", err),
 					}
-					return nil
+					return
 				}
 			}
 		}
@@ -257,18 +257,16 @@ func (a *UserInternalAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.
 		update.SelfSigningKey = &ssk
 	}
 	if update.MasterKey == nil && update.SelfSigningKey == nil {
-		return nil
+		return
 	}
 	if err := a.KeyChangeProducer.ProduceSigningKeyUpdate(update); err != nil {
 		res.Error = &api.KeyError{
 			Err: fmt.Sprintf("a.Producer.ProduceSigningKeyUpdate: %s", err),
 		}
-		return nil
 	}
-	return nil
 }
 
-func (a *UserInternalAPI) PerformUploadDeviceSignatures(ctx context.Context, req *api.PerformUploadDeviceSignaturesRequest, res *api.PerformUploadDeviceSignaturesResponse) error {
+func (a *UserInternalAPI) PerformUploadDeviceSignatures(ctx context.Context, req *api.PerformUploadDeviceSignaturesRequest, res *api.PerformUploadDeviceSignaturesResponse) {
 	// Before we do anything, we need the master and self-signing keys for this user.
 	// Then we can verify the signatures make sense.
 	queryReq := &api.QueryKeysRequest{
@@ -279,7 +277,7 @@ func (a *UserInternalAPI) PerformUploadDeviceSignatures(ctx context.Context, req
 	for userID := range req.Signatures {
 		queryReq.UserToDevices[userID] = []string{}
 	}
-	_ = a.QueryKeys(ctx, queryReq, queryRes)
+	a.QueryKeys(ctx, queryReq, queryRes)
 
 	selfSignatures := map[string]map[gomatrixserverlib.KeyID]fclient.CrossSigningForKeyOrDevice{}
 	otherSignatures := map[string]map[gomatrixserverlib.KeyID]fclient.CrossSigningForKeyOrDevice{}
@@ -325,14 +323,14 @@ func (a *UserInternalAPI) PerformUploadDeviceSignatures(ctx context.Context, req
 		res.Error = &api.KeyError{
 			Err: fmt.Sprintf("a.processSelfSignatures: %s", err),
 		}
-		return nil
+		return
 	}
 
 	if err := a.processOtherSignatures(ctx, req.UserID, queryRes, otherSignatures); err != nil {
 		res.Error = &api.KeyError{
 			Err: fmt.Sprintf("a.processOtherSignatures: %s", err),
 		}
-		return nil
+		return
 	}
 
 	// Finally, generate a notification that we updated the signatures.
@@ -348,10 +346,9 @@ func (a *UserInternalAPI) PerformUploadDeviceSignatures(ctx context.Context, req
 			res.Error = &api.KeyError{
 				Err: fmt.Sprintf("a.Producer.ProduceSigningKeyUpdate: %s", err),
 			}
-			return nil
+			return
 		}
 	}
-	return nil
 }
 
 func (a *UserInternalAPI) processSelfSignatures(
@@ -524,7 +521,7 @@ func (a *UserInternalAPI) crossSigningKeysFromDatabase(
 	}
 }
 
-func (a *UserInternalAPI) QuerySignatures(ctx context.Context, req *api.QuerySignaturesRequest, res *api.QuerySignaturesResponse) error {
+func (a *UserInternalAPI) QuerySignatures(ctx context.Context, req *api.QuerySignaturesRequest, res *api.QuerySignaturesResponse) {
 	for targetUserID, forTargetUser := range req.TargetIDs {
 		keyMap, err := a.KeyDatabase.CrossSigningKeysForUser(ctx, targetUserID)
 		if err != nil && err != sql.ErrNoRows {
@@ -563,7 +560,7 @@ func (a *UserInternalAPI) QuerySignatures(ctx context.Context, req *api.QuerySig
 				res.Error = &api.KeyError{
 					Err: fmt.Sprintf("a.DB.CrossSigningSigsForTarget: %s", err),
 				}
-				return nil
+				return
 			}
 
 			for sourceUserID, forSourceUser := range sigMap {
@@ -585,5 +582,4 @@ func (a *UserInternalAPI) QuerySignatures(ctx context.Context, req *api.QuerySig
 			}
 		}
 	}
-	return nil
 }
diff --git a/userapi/internal/device_list_update.go b/userapi/internal/device_list_update.go
index d60e522e..3fccf56b 100644
--- a/userapi/internal/device_list_update.go
+++ b/userapi/internal/device_list_update.go
@@ -134,7 +134,7 @@ type DeviceListUpdaterDatabase interface {
 }
 
 type DeviceListUpdaterAPI interface {
-	PerformUploadDeviceKeys(ctx context.Context, req *api.PerformUploadDeviceKeysRequest, res *api.PerformUploadDeviceKeysResponse) error
+	PerformUploadDeviceKeys(ctx context.Context, req *api.PerformUploadDeviceKeysRequest, res *api.PerformUploadDeviceKeysResponse)
 }
 
 // KeyChangeProducer is the interface for producers.KeyChange useful for testing.
@@ -519,7 +519,7 @@ func (u *DeviceListUpdater) processServerUser(ctx context.Context, serverName sp
 				uploadReq.SelfSigningKey = *res.SelfSigningKey
 			}
 		}
-		_ = u.api.PerformUploadDeviceKeys(ctx, uploadReq, uploadRes)
+		u.api.PerformUploadDeviceKeys(ctx, uploadReq, uploadRes)
 	}
 	err = u.updateDeviceList(&res)
 	if err != nil {
diff --git a/userapi/internal/device_list_update_test.go b/userapi/internal/device_list_update_test.go
index 4d075e52..10b9c652 100644
--- a/userapi/internal/device_list_update_test.go
+++ b/userapi/internal/device_list_update_test.go
@@ -125,8 +125,7 @@ func (d *mockDeviceListUpdaterDatabase) DeviceKeysJSON(ctx context.Context, keys
 type mockDeviceListUpdaterAPI struct {
 }
 
-func (d *mockDeviceListUpdaterAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.PerformUploadDeviceKeysRequest, res *api.PerformUploadDeviceKeysResponse) error {
-	return nil
+func (d *mockDeviceListUpdaterAPI) PerformUploadDeviceKeys(ctx context.Context, req *api.PerformUploadDeviceKeysRequest, res *api.PerformUploadDeviceKeysResponse) {
 }
 
 type roundTripper struct {
diff --git a/userapi/internal/key_api.go b/userapi/internal/key_api.go
index 0b188b09..786a2dcd 100644
--- a/userapi/internal/key_api.go
+++ b/userapi/internal/key_api.go
@@ -63,7 +63,7 @@ func (a *UserInternalAPI) PerformUploadKeys(ctx context.Context, req *api.Perfor
 	return nil
 }
 
-func (a *UserInternalAPI) PerformClaimKeys(ctx context.Context, req *api.PerformClaimKeysRequest, res *api.PerformClaimKeysResponse) error {
+func (a *UserInternalAPI) PerformClaimKeys(ctx context.Context, req *api.PerformClaimKeysRequest, res *api.PerformClaimKeysResponse) {
 	res.OneTimeKeys = make(map[string]map[string]map[string]json.RawMessage)
 	res.Failures = make(map[string]interface{})
 	// wrap request map in a top-level by-domain map
@@ -110,7 +110,6 @@ func (a *UserInternalAPI) PerformClaimKeys(ctx context.Context, req *api.Perform
 	if len(domainToDeviceKeys) > 0 {
 		a.claimRemoteKeys(ctx, req.Timeout, res, domainToDeviceKeys)
 	}
-	return nil
 }
 
 func (a *UserInternalAPI) claimRemoteKeys(
@@ -228,7 +227,7 @@ func (a *UserInternalAPI) PerformMarkAsStaleIfNeeded(ctx context.Context, req *a
 }
 
 // nolint:gocyclo
-func (a *UserInternalAPI) QueryKeys(ctx context.Context, req *api.QueryKeysRequest, res *api.QueryKeysResponse) error {
+func (a *UserInternalAPI) QueryKeys(ctx context.Context, req *api.QueryKeysRequest, res *api.QueryKeysResponse) {
 	var respMu sync.Mutex
 	res.DeviceKeys = make(map[string]map[string]json.RawMessage)
 	res.MasterKeys = make(map[string]fclient.CrossSigningKey)
@@ -252,7 +251,7 @@ func (a *UserInternalAPI) QueryKeys(ctx context.Context, req *api.QueryKeysReque
 				res.Error = &api.KeyError{
 					Err: fmt.Sprintf("failed to query local device keys: %s", err),
 				}
-				return nil
+				return
 			}
 
 			// pull out display names after we have the keys so we handle wildcards correctly
@@ -330,7 +329,7 @@ func (a *UserInternalAPI) QueryKeys(ctx context.Context, req *api.QueryKeysReque
 				// Stop executing the function if the context was canceled/the deadline was exceeded,
 				// as we can't continue without a valid context.
 				if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
-					return nil
+					return
 				}
 				logrus.WithError(err).Errorf("a.KeyDatabase.CrossSigningSigsForTarget failed")
 				continue
@@ -356,7 +355,7 @@ func (a *UserInternalAPI) QueryKeys(ctx context.Context, req *api.QueryKeysReque
 				// Stop executing the function if the context was canceled/the deadline was exceeded,
 				// as we can't continue without a valid context.
 				if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
-					return nil
+					return
 				}
 				logrus.WithError(err).Errorf("a.KeyDatabase.CrossSigningSigsForTarget failed")
 				continue
@@ -384,7 +383,6 @@ func (a *UserInternalAPI) QueryKeys(ctx context.Context, req *api.QueryKeysReque
 			}
 		}
 	}
-	return nil
 }
 
 func (a *UserInternalAPI) remoteKeysFromDatabase(
diff --git a/userapi/internal/user_api.go b/userapi/internal/user_api.go
index ea97fd35..32f3d84b 100644
--- a/userapi/internal/user_api.go
+++ b/userapi/internal/user_api.go
@@ -25,7 +25,6 @@ import (
 
 	appserviceAPI "github.com/matrix-org/dendrite/appservice/api"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
-	"github.com/matrix-org/dendrite/clientapi/jsonerror"
 	fedsenderapi "github.com/matrix-org/dendrite/federationapi/api"
 	"github.com/matrix-org/dendrite/internal/pushrules"
 	"github.com/matrix-org/gomatrixserverlib"
@@ -715,7 +714,7 @@ func (a *UserInternalAPI) uploadBackupKeys(ctx context.Context, req *api.Perform
 		return res, fmt.Errorf("backup was deleted")
 	}
 	if version != req.Version {
-		return res, jsonerror.WrongBackupVersionError(version)
+		return res, spec.WrongBackupVersionError(version)
 	}
 	res.Exists = true
 	res.Version = version