Move json errors over to gmsl (#3080)

50 files changed, 427 insertions, 743 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))