Merge 07cef68485 into 0b5db68242

changelogs/application_service/newsfragments/2330.clarification

@@ -0,0 +1 @@
+Fix various typos throughout the specification.

changelogs/client_server/newsfragments/2315.feature

@@ -0,0 +1 @@
+Add `M_USER_LIMIT_EXCEEDED` common error code, as per [MSC4335](https://github.com/matrix-org/matrix-spec-proposals/pull/4335).

content/application-service-api.md

@@ -84,7 +84,7 @@ For the `users` namespace, application services can only register interest in
 homeserver). Events affecting users on other homeservers are not sent to an application
 service, even if the user happens to match the one of the `users` namespaces (unless,
 of course, the event affects a room that the application service is interested in
-for another room - for example, because there is another user in the room that the
+for another reason - for example, because there is another user in the room that the
 application service is interested in).
 
 For the `rooms` and `aliases` namespaces, all events in a matching room will be

content/client-server-api/_index.md

@@ -147,6 +147,37 @@ state (e.g.: sending messages, account data, etc) and not routes which
 only read state (e.g.: [`/sync`](#get_matrixclientv3sync),
 [`/user/{userId}/account_data/{type}`](#get_matrixclientv3useruseridaccount_datatype), etc).
 
+`M_USER_LIMIT_EXCEEDED`
+: {{% added-in v="1.18" %}} The request cannot be completed because the user has
+exceeded (or the request would cause them to exceed) a limit associated with
+their account. For example, a user may have reached their allocated storage
+quota, reached a maximum number of allowed rooms, devices, or other
+account-scoped resources, or exceeded usage limits for specific features.
+
+: The error response MUST have an `info_uri` field (string), which is a URI
+that the client can present to the user to provide more context on the
+encountered limit and, if applicable, guidance on how to increase the limit.
+The homeserver MAY return different values for `info_uri` depending on the type
+of limit reached.
+
+: The error response MAY include a `can_upgrade` field (boolean, default `false`).
+If `true`, it indicates that the specific limit encountered can be increased,
+for example by upgrading the user's account tier. If absent or `false`, the
+limit is a hard limit that cannot be increased.
+
+: The HTTP status code will depend on depend on the particular endpoint.
+
+: Example response:
+
+  ```json
+  {
+    "errcode": "M_USER_LIMIT_EXCEEDED",
+    "error": "You have exceeded your storage quota of 10GB",
+    "info_uri": "https://example.com/homeserver/about?limit_type=quota",
+    "can_upgrade": true
+  }
+  ```
+
 `M_UNKNOWN`
 : An unknown error has occurred.