Remove redundant types from comments. (#14412)

Remove type hints from comments which have been added
as Python type hints. This helps avoid drift between comments
and reality, as well as removing redundant information.

Also adds some missing type hints which were simple to fill in.

49 files changed, 143 insertions, 150 deletions

diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index 400dd12aba..e2cfcea0f2 100644
--- a/synapse/api/errors.py
+++ b/synapse/api/errors.py
@@ -713,7 +713,7 @@ class HttpResponseException(CodeMessageException):
         set to the reason code from the HTTP response.
 
         Returns:
-            SynapseError:
+            The error converted to a SynapseError.
         """
         # try to parse the body as json, to get better errcode/msg, but
         # default to M_UNKNOWN with the HTTP status as the error text
diff --git a/synapse/config/logger.py b/synapse/config/logger.py
index 94d1150415..5468b963a2 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -317,10 +317,9 @@ def setup_logging(
     Set up the logging subsystem.
 
     Args:
-        config (LoggingConfig | synapse.config.worker.WorkerConfig):
-            configuration data
+        config: configuration data
 
-        use_worker_options (bool): True to use the 'worker_log_config' option
+        use_worker_options: True to use the 'worker_log_config' option
             instead of 'log_config'.
 
         logBeginner: The Twisted logBeginner to use.
diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index c88afb2986..dd9b8089ec 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -213,7 +213,7 @@ class Keyring:
 
     def verify_json_objects_for_server(
         self, server_and_json: Iterable[Tuple[str, dict, int]]
-    ) -> List[defer.Deferred]:
+    ) -> List["defer.Deferred[None]"]:
         """Bulk verifies signatures of json objects, bulk fetching keys as
         necessary.
 
@@ -226,10 +226,9 @@ class Keyring:
                 valid.
 
         Returns:
-            List<Deferred[None]>: for each input triplet, a deferred indicating success
-                or failure to verify each json object's signature for the given
-                server_name. The deferreds run their callbacks in the sentinel
-                logcontext.
+            For each input triplet, a deferred indicating success or failure to
+            verify each json object's signature for the given server_name. The
+            deferreds run their callbacks in the sentinel logcontext.
         """
         return [
             run_in_background(
diff --git a/synapse/events/__init__.py b/synapse/events/__init__.py
index 030c3ca408..8aca9a3ab9 100644
--- a/synapse/events/__init__.py
+++ b/synapse/events/__init__.py
@@ -597,8 +597,7 @@ def _event_type_from_format_version(
         format_version: The event format version
 
     Returns:
-        type: A type that can be initialized as per the initializer of
-        `FrozenEvent`
+        A type that can be initialized as per the initializer of `FrozenEvent`
     """
 
     if format_version == EventFormatVersions.ROOM_V1_V2:
diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py
index cd39d4d111..a3cfc701cd 100644
--- a/synapse/federation/transport/client.py
+++ b/synapse/federation/transport/client.py
@@ -280,12 +280,11 @@ class TransportLayerClient:
         Note that this does not append any events to any graphs.
 
         Args:
-            destination (str): address of remote homeserver
-            room_id (str): room to join/leave
-            user_id (str): user to be joined/left
-            membership (str): one of join/leave
-            params (dict[str, str|Iterable[str]]): Query parameters to include in the
-                request.
+            destination: address of remote homeserver
+            room_id: room to join/leave
+            user_id: user to be joined/left
+            membership: one of join/leave
+            params: Query parameters to include in the request.
 
         Returns:
             Succeeds when we get a 2xx HTTP response. The result
diff --git a/synapse/federation/transport/server/_base.py b/synapse/federation/transport/server/_base.py
index 1db8009d6c..cdaf0d5de7 100644
--- a/synapse/federation/transport/server/_base.py
+++ b/synapse/federation/transport/server/_base.py
@@ -224,10 +224,10 @@ class BaseFederationServlet:
 
         With arguments:
 
-            origin (unicode|None): The authenticated server_name of the calling server,
+            origin (str|None): The authenticated server_name of the calling server,
                 unless REQUIRE_AUTH is set to False and authentication failed.
 
-            content (unicode|None): decoded json body of the request. None if the
+            content (str|None): decoded json body of the request. None if the
                 request was a GET.
 
             query (dict[bytes, list[bytes]]): Query params from the request. url-decoded
diff --git a/synapse/handlers/e2e_keys.py b/synapse/handlers/e2e_keys.py
index a9912c467d..bf1221f523 100644
--- a/synapse/handlers/e2e_keys.py
+++ b/synapse/handlers/e2e_keys.py
@@ -870,7 +870,7 @@ class E2eKeysHandler:
         - signatures of the user's master key by the user's devices.
 
         Args:
-            user_id (string): the user uploading the keys
+            user_id: the user uploading the keys
             signatures (dict[string, dict]): map of devices to signed keys
 
         Returns:
diff --git a/synapse/handlers/e2e_room_keys.py b/synapse/handlers/e2e_room_keys.py
index 28dc08c22a..83f53ceb88 100644
--- a/synapse/handlers/e2e_room_keys.py
+++ b/synapse/handlers/e2e_room_keys.py
@@ -377,8 +377,9 @@ class E2eRoomKeysHandler:
         """Deletes a given version of the user's e2e_room_keys backup
 
         Args:
-            user_id(str): the user whose current backup version we're deleting
-            version(str): the version id of the backup being deleted
+            user_id: the user whose current backup version we're deleting
+            version: Optional. the version ID of the backup version we're deleting
+                If missing, we delete the current backup version info.
         Raises:
             NotFoundError: if this backup version doesn't exist
         """
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 5fc3b8bc8c..188f0956ef 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -1596,8 +1596,8 @@ class FederationHandler:
         Fetch the complexity of a remote room over federation.
 
         Args:
-            remote_room_hosts (list[str]): The remote servers to ask.
-            room_id (str): The room ID to ask about.
+            remote_room_hosts: The remote servers to ask.
+            room_id: The room ID to ask about.
 
         Returns:
             Dict contains the complexity
diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py
index 93d09e9939..848e46eb9b 100644
--- a/synapse/handlers/identity.py
+++ b/synapse/handlers/identity.py
@@ -711,7 +711,7 @@ class IdentityHandler:
             inviter_display_name: The current display name of the
                 inviter.
             inviter_avatar_url: The URL of the inviter's avatar.
-            id_access_token (str): The access token to authenticate to the identity
+            id_access_token: The access token to authenticate to the identity
                 server with
 
         Returns:
diff --git a/synapse/handlers/oidc.py b/synapse/handlers/oidc.py
index 867973dcca..41c675f408 100644
--- a/synapse/handlers/oidc.py
+++ b/synapse/handlers/oidc.py
@@ -787,7 +787,7 @@ class OidcProvider:
                 Must include an ``access_token`` field.
 
         Returns:
-            UserInfo: an object representing the user.
+            an object representing the user.
         """
         logger.debug("Using the OAuth2 access_token to request userinfo")
         metadata = await self.load_metadata()
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index 0066d63987..b7bc787636 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -201,7 +201,7 @@ class BasePresenceHandler(abc.ABC):
         """Get the current presence state for multiple users.
 
         Returns:
-            dict: `user_id` -> `UserPresenceState`
+            A mapping of `user_id` -> `UserPresenceState`
         """
         states = {}
         missing = []
diff --git a/synapse/handlers/saml.py b/synapse/handlers/saml.py
index 9602f0d0bb..874860d461 100644
--- a/synapse/handlers/saml.py
+++ b/synapse/handlers/saml.py
@@ -441,7 +441,7 @@ class DefaultSamlMappingProvider:
             client_redirect_url: where the client wants to redirect to
 
         Returns:
-            dict: A dict containing new user attributes. Possible keys:
+            A dict containing new user attributes. Possible keys:
                 * mxid_localpart (str): Required. The localpart of the user's mxid
                 * displayname (str): The displayname of the user
                 * emails (list[str]): Any emails for the user
@@ -483,7 +483,7 @@ class DefaultSamlMappingProvider:
         Args:
             config: A dictionary containing configuration options for this provider
         Returns:
-            SamlConfig: A custom config object for this module
+            A custom config object for this module
         """
         # Parse config options and use defaults where necessary
         mxid_source_attribute = config.get("mxid_source_attribute", "uid")
diff --git a/synapse/http/additional_resource.py b/synapse/http/additional_resource.py
index 6a9f6635d2..8729630581 100644
--- a/synapse/http/additional_resource.py
+++ b/synapse/http/additional_resource.py
@@ -45,8 +45,7 @@ class AdditionalResource(DirectServeJsonResource):
 
         Args:
             hs: homeserver
-            handler ((twisted.web.server.Request) -> twisted.internet.defer.Deferred):
-                function to be called to handle the request.
+            handler: function to be called to handle the request.
         """
         super().__init__()
         self._handler = handler
diff --git a/synapse/http/federation/matrix_federation_agent.py b/synapse/http/federation/matrix_federation_agent.py
index 2f0177f1e2..0359231e7d 100644
--- a/synapse/http/federation/matrix_federation_agent.py
+++ b/synapse/http/federation/matrix_federation_agent.py
@@ -155,11 +155,10 @@ class MatrixFederationAgent:
                 a file for a file upload).  Or None if the request is to have
                 no body.
         Returns:
-            Deferred[twisted.web.iweb.IResponse]:
-                fires when the header of the response has been received (regardless of the
-                response status code). Fails if there is any problem which prevents that
-                response from being received (including problems that prevent the request
-                from being sent).
+            A deferred which fires when the header of the response has been received
+            (regardless of the response status code). Fails if there is any problem
+            which prevents that response from being received (including problems that
+            prevent the request from being sent).
         """
         # We use urlparse as that will set `port` to None if there is no
         # explicit port.
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index 3c35b1d2c7..b92f1d3d1a 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -951,8 +951,7 @@ class MatrixFederationHttpClient:
 
             args: query params
         Returns:
-            dict|list: Succeeds when we get a 2xx HTTP response. The
-            result will be the decoded JSON body.
+            Succeeds when we get a 2xx HTTP response. The result will be the decoded JSON body.
 
         Raises:
             HttpResponseException: If we get an HTTP response code >= 300
diff --git a/synapse/http/proxyagent.py b/synapse/http/proxyagent.py
index 1f8227896f..18899bc6d1 100644
--- a/synapse/http/proxyagent.py
+++ b/synapse/http/proxyagent.py
@@ -34,7 +34,7 @@ from twisted.web.client import (
 )
 from twisted.web.error import SchemeNotSupported
 from twisted.web.http_headers import Headers
-from twisted.web.iweb import IAgent, IBodyProducer, IPolicyForHTTPS
+from twisted.web.iweb import IAgent, IBodyProducer, IPolicyForHTTPS, IResponse
 
 from synapse.http import redact_uri
 from synapse.http.connectproxyclient import HTTPConnectProxyEndpoint, ProxyCredentials
@@ -134,7 +134,7 @@ class ProxyAgent(_AgentBase):
         uri: bytes,
         headers: Optional[Headers] = None,
         bodyProducer: Optional[IBodyProducer] = None,
-    ) -> defer.Deferred:
+    ) -> "defer.Deferred[IResponse]":
         """
         Issue a request to the server indicated by the given uri.
 
@@ -157,17 +157,17 @@ class ProxyAgent(_AgentBase):
                 a file upload). Or, None if the request is to have no body.
 
         Returns:
-            Deferred[IResponse]: completes when the header of the response has
-                 been received (regardless of the response status code).
+            A deferred which completes when the header of the response has
+            been received (regardless of the response status code).
 
-                 Can fail with:
-                    SchemeNotSupported: if the uri is not http or https
+            Can fail with:
+                SchemeNotSupported: if the uri is not http or https
 
-                    twisted.internet.error.TimeoutError if the server we are connecting
-                        to (proxy or destination) does not accept a connection before
-                        connectTimeout.
+                twisted.internet.error.TimeoutError if the server we are connecting
+                    to (proxy or destination) does not accept a connection before
+                    connectTimeout.
 
-                    ... other things too.
+                ... other things too.
         """
         uri = uri.strip()
         if not _VALID_URI.match(uri):
diff --git a/synapse/http/server.py b/synapse/http/server.py
index b26e34bceb..051a1899a0 100644
--- a/synapse/http/server.py
+++ b/synapse/http/server.py
@@ -267,7 +267,7 @@ class HttpServer(Protocol):
                 request. The first argument will be the request object and
                 subsequent arguments will be any matched groups from the regex.
                 This should return either tuple of (code, response), or None.
-            servlet_classname (str): The name of the handler to be used in prometheus
+            servlet_classname: The name of the handler to be used in prometheus
                 and opentracing logs.
         """
 
diff --git a/synapse/http/site.py b/synapse/http/site.py
index 3dbd541fed..6a1dbf7f33 100644
--- a/synapse/http/site.py
+++ b/synapse/http/site.py
@@ -400,7 +400,7 @@ class SynapseRequest(Request):
         be sure to call finished_processing.
 
         Args:
-            servlet_name (str): the name of the servlet which will be
+            servlet_name: the name of the servlet which will be
                 processing this request. This is used in the metrics.
 
                 It is possible to update this afterwards by updating
diff --git a/synapse/logging/context.py b/synapse/logging/context.py
index 6a08ffed64..f62bea968f 100644
--- a/synapse/logging/context.py
+++ b/synapse/logging/context.py
@@ -117,8 +117,7 @@ class ContextResourceUsage:
         """Create a new ContextResourceUsage
 
         Args:
-            copy_from (ContextResourceUsage|None): if not None, an object to
-                copy stats from
+            copy_from: if not None, an object to copy stats from
         """
         if copy_from is None:
             self.reset()
@@ -162,7 +161,7 @@ class ContextResourceUsage:
         """Add another ContextResourceUsage's stats to this one's.
 
         Args:
-            other (ContextResourceUsage): the other resource usage object
+            other: the other resource usage object
         """
         self.ru_utime += other.ru_utime
         self.ru_stime += other.ru_stime
@@ -342,7 +341,7 @@ class LoggingContext:
         called directly.
 
         Returns:
-            LoggingContext: the current logging context
+            The current logging context
         """
         warnings.warn(
             "synapse.logging.context.LoggingContext.current_context() is deprecated "
@@ -362,7 +361,8 @@ class LoggingContext:
         called directly.
 
         Args:
-            context(LoggingContext): The context to activate.
+            context: The context to activate.
+
         Returns:
             The context that was previously active
         """
@@ -474,8 +474,7 @@ class LoggingContext:
         """Get resources used by this logcontext so far.
 
         Returns:
-            ContextResourceUsage: a *copy* of the object tracking resource
-                usage so far
+            A *copy* of the object tracking resource usage so far
         """
         # we always return a copy, for consistency
         res = self._resource_usage.copy()
@@ -663,7 +662,8 @@ def current_context() -> LoggingContextOrSentinel:
 def set_current_context(context: LoggingContextOrSentinel) -> LoggingContextOrSentinel:
     """Set the current logging context in thread local storage
     Args:
-        context(LoggingContext): The context to activate.
+        context: The context to activate.
+
     Returns:
         The context that was previously active
     """
@@ -700,7 +700,7 @@ def nested_logging_context(suffix: str) -> LoggingContext:
         suffix: suffix to add to the parent context's 'name'.
 
     Returns:
-        LoggingContext: new logging context.
+        A new logging context.
     """
     curr_context = current_context()
     if not curr_context:
@@ -898,20 +898,19 @@ def defer_to_thread(
     on it.
 
     Args:
-        reactor (twisted.internet.base.ReactorBase): The reactor in whose main thread
-            the Deferred will be invoked, and whose threadpool we should use for the
-            function.
+        reactor: The reactor in whose main thread the Deferred will be invoked,
+            and whose threadpool we should use for the function.
 
             Normally this will be hs.get_reactor().
 
-        f (callable): The function to call.
+        f: The function to call.
 
         args: positional arguments to pass to f.
 
         kwargs: keyword arguments to pass to f.
 
     Returns:
-        Deferred: A Deferred which fires a callback with the result of `f`, or an
+        A Deferred which fires a callback with the result of `f`, or an
             errback if `f` throws an exception.
     """
     return defer_to_threadpool(reactor, reactor.getThreadPool(), f, *args, **kwargs)
@@ -939,20 +938,20 @@ def defer_to_threadpool(
     on it.
 
     Args:
-        reactor (twisted.internet.base.ReactorBase): The reactor in whose main thread
-            the Deferred will be invoked. Normally this will be hs.get_reactor().
+        reactor: The reactor in whose main thread the Deferred will be invoked.
+            Normally this will be hs.get_reactor().
 
-        threadpool (twisted.python.threadpool.ThreadPool): The threadpool to use for
-            running `f`. Normally this will be hs.get_reactor().getThreadPool().
+        threadpool: The threadpool to use for running `f`. Normally this will be
+            hs.get_reactor().getThreadPool().
 
-        f (callable): The function to call.
+        f: The function to call.
 
         args: positional arguments to pass to f.
 
         kwargs: keyword arguments to pass to f.
 
     Returns:
-        Deferred: A Deferred which fires a callback with the result of `f`, or an
+        A Deferred which fires a callback with the result of `f`, or an
             errback if `f` throws an exception.
     """
     curr_context = current_context()
diff --git a/synapse/logging/opentracing.py b/synapse/logging/opentracing.py
index 8ce5a2a338..b69060854f 100644
--- a/synapse/logging/opentracing.py
+++ b/synapse/logging/opentracing.py
@@ -721,7 +721,7 @@ def inject_header_dict(
         destination: address of entity receiving the span context. Must be given unless
             check_destination is False. The context will only be injected if the
             destination matches the opentracing whitelist
-        check_destination (bool): If false, destination will be ignored and the context
+        check_destination: If false, destination will be ignored and the context
             will always be injected.
 
     Note:
@@ -780,7 +780,7 @@ def get_active_span_text_map(destination: Optional[str] = None) -> Dict[str, str
         destination: the name of the remote server.
 
     Returns:
-        dict: the active span's context if opentracing is enabled, otherwise empty.
+        the active span's context if opentracing is enabled, otherwise empty.
     """
 
     if destination and not whitelisted_homeserver(destination):
diff --git a/synapse/module_api/__init__.py b/synapse/module_api/__init__.py
index 30e689d00d..1adc1fd64f 100644
--- a/synapse/module_api/__init__.py
+++ b/synapse/module_api/__init__.py
@@ -787,7 +787,7 @@ class ModuleApi:
         Added in Synapse v0.25.0.
 
         Args:
-            access_token(str): access token
+            access_token: access token
 
         Returns:
             twisted.internet.defer.Deferred - resolves once the access token
@@ -832,7 +832,7 @@ class ModuleApi:
             **kwargs: named args to be passed to func
 
         Returns:
-            Deferred[object]: result of func
+            Result of func
         """
         # type-ignore: See https://github.com/python/mypy/issues/8862
         return defer.ensureDeferred(
@@ -924,8 +924,7 @@ class ModuleApi:
                 to represent 'any') of the room state to acquire.
 
         Returns:
-            twisted.internet.defer.Deferred[list(synapse.events.FrozenEvent)]:
-                The filtered state events in the room.
+            The filtered state events in the room.
         """
         state_ids = yield defer.ensureDeferred(
             self._storage_controllers.state.get_current_state_ids(
diff --git a/synapse/replication/http/_base.py b/synapse/replication/http/_base.py
index 5e661f8c73..3f4d3fc51a 100644
--- a/synapse/replication/http/_base.py
+++ b/synapse/replication/http/_base.py
@@ -153,7 +153,7 @@ class ReplicationEndpoint(metaclass=abc.ABCMeta):
         argument list.
 
         Returns:
-            dict: If POST/PUT request then dictionary must be JSON serialisable,
+            If POST/PUT request then dictionary must be JSON serialisable,
             otherwise must be appropriate for adding as query args.
         """
         return {}
diff --git a/synapse/rest/admin/users.py b/synapse/rest/admin/users.py
index 1951b8a9f2..6e0c44be2a 100644
--- a/synapse/rest/admin/users.py
+++ b/synapse/rest/admin/users.py
@@ -903,8 +903,9 @@ class PushersRestServlet(RestServlet):
         @user:server/pushers
 
     Returns:
-        pushers: Dictionary containing pushers information.
-        total: Number of pushers in dictionary `pushers`.
+        A dictionary with keys:
+            pushers: Dictionary containing pushers information.
+            total: Number of pushers in dictionary `pushers`.
     """
 
     PATTERNS = admin_patterns("/users/(?P<user_id>[^/]*)/pushers$")
diff --git a/synapse/rest/client/login.py b/synapse/rest/client/login.py
index 05706b598c..8adced41e5 100644
--- a/synapse/rest/client/login.py
+++ b/synapse/rest/client/login.py
@@ -350,7 +350,7 @@ class LoginRestServlet(RestServlet):
             auth_provider_session_id: The session ID got during login from the SSO IdP.
 
         Returns:
-            result: Dictionary of account information after successful login.
+            Dictionary of account information after successful login.
         """
 
         # Before we actually log them in we check if they've already logged in
diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index 328c0c5477..40b0d39eb2 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -344,8 +344,8 @@ class MediaRepository:
         download from remote server.
 
         Args:
-            server_name (str): Remote server_name where the media originated.
-            media_id (str): The media ID of the content (as defined by the
+            server_name: Remote server_name where the media originated.
+            media_id: The media ID of the content (as defined by the
                 remote server).
 
         Returns:
diff --git a/synapse/rest/media/v1/thumbnailer.py b/synapse/rest/media/v1/thumbnailer.py
index 9b93b9b4f6..a48a4de92a 100644
--- a/synapse/rest/media/v1/thumbnailer.py
+++ b/synapse/rest/media/v1/thumbnailer.py
@@ -138,7 +138,7 @@ class Thumbnailer:
         """Rescales the image to the given dimensions.
 
         Returns:
-            BytesIO: the bytes of the encoded image ready to be written to disk
+            The bytes of the encoded image ready to be written to disk
         """
         with self._resize(width, height) as scaled:
             return self._encode_image(scaled, output_type)
@@ -155,7 +155,7 @@ class Thumbnailer:
             max_height: The largest possible height.
 
         Returns:
-            BytesIO: the bytes of the encoded image ready to be written to disk
+            The bytes of the encoded image ready to be written to disk
         """
         if width * self.height > height * self.width:
             scaled_width = width
diff --git a/synapse/server_notices/consent_server_notices.py b/synapse/server_notices/consent_server_notices.py
index 698ca742ed..94025ba41f 100644
--- a/synapse/server_notices/consent_server_notices.py
+++ b/synapse/server_notices/consent_server_notices.py
@@ -113,9 +113,8 @@ def copy_with_str_subst(x: Any, substitutions: Any) -> Any:
     """Deep-copy a structure, carrying out string substitutions on any strings
 
     Args:
-        x (object): structure to be copied
-        substitutions (object): substitutions to be made - passed into the
-            string '%' operator
+        x: structure to be copied
+        substitutions: substitutions to be made - passed into the string '%' operator
 
     Returns:
         copy of x
diff --git a/synapse/server_notices/resource_limits_server_notices.py b/synapse/server_notices/resource_limits_server_notices.py
index 3134cd2d3d..a31a2c99a7 100644
--- a/synapse/server_notices/resource_limits_server_notices.py
+++ b/synapse/server_notices/resource_limits_server_notices.py
@@ -170,11 +170,13 @@ class ResourceLimitsServerNotices:
             room_id: The room id of the server notices room
 
         Returns:
-            bool: Is the room currently blocked
-            list: The list of pinned event IDs that are unrelated to limit blocking
-            This list can be used as a convenience in the case where the block
-            is to be lifted and the remaining pinned event references need to be
-            preserved
+            Tuple of:
+                Is the room currently blocked
+
+                The list of pinned event IDs that are unrelated to limit blocking
+                This list can be used as a convenience in the case where the block
+                is to be lifted and the remaining pinned event references need to be
+                preserved
         """
         currently_blocked = False
         pinned_state_event = None
diff --git a/synapse/storage/controllers/persist_events.py b/synapse/storage/controllers/persist_events.py
index 48976dc570..33ffef521b 100644
--- a/synapse/storage/controllers/persist_events.py
+++ b/synapse/storage/controllers/persist_events.py
@@ -204,9 +204,8 @@ class _EventPeristenceQueue(Generic[_PersistResult]):
         process to to so, calling the per_item_callback for each item.
 
         Args:
-            room_id (str):
-            task (_EventPersistQueueTask): A _PersistEventsTask or
-                _UpdateCurrentStateTask to process.
+            room_id:
+            task: A _PersistEventsTask or _UpdateCurrentStateTask to process.
 
         Returns:
             the result returned by the `_per_item_callback` passed to
diff --git a/synapse/storage/databases/main/devices.py b/synapse/storage/databases/main/devices.py
index aa58c2adc3..e114c733d1 100644
--- a/synapse/storage/databases/main/devices.py
+++ b/synapse/storage/databases/main/devices.py
@@ -535,7 +535,7 @@ class DeviceWorkerStore(RoomMemberWorkerStore, EndToEndKeyWorkerStore):
             limit: Maximum number of device updates to return
 
         Returns:
-            List: List of device update tuples:
+            List of device update tuples:
                 - user_id
                 - device_id
                 - stream_id
diff --git a/synapse/storage/databases/main/e2e_room_keys.py b/synapse/storage/databases/main/e2e_room_keys.py
index af59be6b48..6240f9a75e 100644
--- a/synapse/storage/databases/main/e2e_room_keys.py
+++ b/synapse/storage/databases/main/e2e_room_keys.py
@@ -391,10 +391,10 @@ class EndToEndRoomKeyStore(SQLBaseStore):
         Returns:
             A dict giving the info metadata for this backup version, with
             fields including:
-                version(str)
-                algorithm(str)
-                auth_data(object): opaque dict supplied by the client
-                etag(int): tag of the keys in the backup
+                version (str)
+                algorithm (str)
+                auth_data (object): opaque dict supplied by the client
+                etag (int): tag of the keys in the backup
         """
 
         def _get_e2e_room_keys_version_info_txn(txn: LoggingTransaction) -> JsonDict:
diff --git a/synapse/storage/databases/main/end_to_end_keys.py b/synapse/storage/databases/main/end_to_end_keys.py
index 2a4f58ed92..cf33e73e2b 100644
--- a/synapse/storage/databases/main/end_to_end_keys.py
+++ b/synapse/storage/databases/main/end_to_end_keys.py
@@ -412,10 +412,9 @@ class EndToEndKeyWorkerStore(EndToEndKeyBackgroundStore, CacheInvalidationWorker
         """Retrieve a number of one-time keys for a user
 
         Args:
-            user_id(str): id of user to get keys for
-            device_id(str): id of device to get keys for
-            key_ids(list[str]): list of key ids (excluding algorithm) to
-                retrieve
+            user_id: id of user to get keys for
+            device_id: id of device to get keys for
+            key_ids: list of key ids (excluding algorithm) to retrieve
 
         Returns:
             A map from (algorithm, key_id) to json string for key
diff --git a/synapse/storage/databases/main/events.py b/synapse/storage/databases/main/events.py
index c4acff5be6..d68f127f9b 100644
--- a/synapse/storage/databases/main/events.py
+++ b/synapse/storage/databases/main/events.py
@@ -1279,9 +1279,10 @@ class PersistEventsStore:
         Pick the earliest non-outlier if there is one, else the earliest one.
 
         Args:
-            events_and_contexts (list[(EventBase, EventContext)]):
+            events_and_contexts:
+
         Returns:
-            list[(EventBase, EventContext)]: filtered list
+            filtered list
         """
         new_events_and_contexts: OrderedDict[
             str, Tuple[EventBase, EventContext]
@@ -1307,9 +1308,8 @@ class PersistEventsStore:
         """Update min_depth for each room
 
         Args:
-            txn (twisted.enterprise.adbapi.Connection): db connection
-            events_and_contexts (list[(EventBase, EventContext)]): events
-                we are persisting
+            txn: db connection
+            events_and_contexts: events we are persisting
         """
         depth_updates: Dict[str, int] = {}
         for event, context in events_and_contexts:
@@ -1580,13 +1580,11 @@ class PersistEventsStore:
         """Update all the miscellaneous tables for new events
 
         Args:
-            txn (twisted.enterprise.adbapi.Connection): db connection
-            events_and_contexts (list[(EventBase, EventContext)]): events
-                we are persisting
-            all_events_and_contexts (list[(EventBase, EventContext)]): all
-                events that we were going to persist. This includes events
-                we've already persisted, etc, that wouldn't appear in
-                events_and_context.
+            txn: db connection
+            events_and_contexts: events we are persisting
+            all_events_and_contexts: all events that we were going to persist.
+                This includes events we've already persisted, etc, that wouldn't
+                appear in events_and_context.
             inhibit_local_membership_updates: Stop the local_current_membership
                 from being updated by these events. This should be set to True
                 for backfilled events because backfilled events in the past do
diff --git a/synapse/storage/databases/main/events_worker.py b/synapse/storage/databases/main/events_worker.py
index 467d20253d..8a104f7e93 100644
--- a/synapse/storage/databases/main/events_worker.py
+++ b/synapse/storage/databases/main/events_worker.py
@@ -1589,7 +1589,7 @@ class EventsWorkerStore(SQLBaseStore):
             room_id: The room ID to query.
 
         Returns:
-            dict[str:float] of complexity version to complexity.
+            Map of complexity version to complexity.
         """
         state_events = await self.get_current_state_event_counts(room_id)
 
diff --git a/synapse/storage/databases/main/monthly_active_users.py b/synapse/storage/databases/main/monthly_active_users.py
index efd136a864..db9a24db5e 100644
--- a/synapse/storage/databases/main/monthly_active_users.py
+++ b/synapse/storage/databases/main/monthly_active_users.py
@@ -217,7 +217,7 @@ class MonthlyActiveUsersWorkerStore(RegistrationWorkerStore):
         def _reap_users(txn: LoggingTransaction, reserved_users: List[str]) -> None:
             """
             Args:
-                reserved_users (tuple): reserved users to preserve
+                reserved_users: reserved users to preserve
             """
 
             thirty_days_ago = int(self._clock.time_msec()) - (1000 * 60 * 60 * 24 * 30)
@@ -370,8 +370,8 @@ class MonthlyActiveUsersWorkerStore(RegistrationWorkerStore):
         should not appear in the MAU stats).
 
         Args:
-            txn (cursor):
-            user_id (str): user to add/update
+            txn:
+            user_id: user to add/update
         """
         assert (
             self._update_on_this_worker
@@ -401,7 +401,7 @@ class MonthlyActiveUsersWorkerStore(RegistrationWorkerStore):
         add the user to the monthly active tables
 
         Args:
-            user_id(str): the user_id to query
+            user_id: the user_id to query
         """
         assert (
             self._update_on_this_worker
diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
index 5167089e03..31f0f2bd3d 100644
--- a/synapse/storage/databases/main/registration.py
+++ b/synapse/storage/databases/main/registration.py
@@ -953,7 +953,7 @@ class RegistrationWorkerStore(CacheInvalidationWorkerStore):
         """Returns user id from threepid
 
         Args:
-            txn (cursor):
+            txn:
             medium: threepid medium e.g. email
             address: threepid address e.g. me@example.com
 
@@ -1283,8 +1283,8 @@ class RegistrationWorkerStore(CacheInvalidationWorkerStore):
         """Sets an expiration date to the account with the given user ID.
 
         Args:
-             user_id (str): User ID to set an expiration date for.
-             use_delta (bool): If set to False, the expiration date for the user will be
+             user_id: User ID to set an expiration date for.
+             use_delta: If set to False, the expiration date for the user will be
                 now + validity period. If set to True, this expiration date will be a
                 random value in the [now + period - d ; now + period] range, d being a
                 delta equal to 10% of the validity period.
diff --git a/synapse/storage/databases/main/room.py b/synapse/storage/databases/main/room.py
index 7d97f8f60e..4fbaefad73 100644
--- a/synapse/storage/databases/main/room.py
+++ b/synapse/storage/databases/main/room.py
@@ -2057,7 +2057,8 @@ class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore):
         Args:
             report_id: ID of reported event in database
         Returns:
-            event_report: json list of information from event report
+            JSON dict of information from an event report or None if the
+            report does not exist.
         """
 
         def _get_event_report_txn(
@@ -2130,8 +2131,9 @@ class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore):
             user_id: search for user_id. Ignored if user_id is None
             room_id: search for room_id. Ignored if room_id is None
         Returns:
-            event_reports: json list of event reports
-            count: total number of event reports matching the filter criteria
+            Tuple of:
+                json list of event reports
+                total number of event reports matching the filter criteria
         """
 
         def _get_event_reports_paginate_txn(
diff --git a/synapse/storage/databases/main/user_directory.py b/synapse/storage/databases/main/user_directory.py
index ddb25b5cea..698d6f7515 100644
--- a/synapse/storage/databases/main/user_directory.py
+++ b/synapse/storage/databases/main/user_directory.py
@@ -185,9 +185,8 @@ class UserDirectoryBackgroundUpdateStore(StateDeltasStore):
         - who should be in the user_directory.
 
         Args:
-            progress (dict)
-            batch_size (int): Maximum number of state events to process
-                per cycle.
+            progress
+            batch_size: Maximum number of state events to process per cycle.
 
         Returns:
             number of events processed.
@@ -708,10 +707,10 @@ class UserDirectoryStore(UserDirectoryBackgroundUpdateStore):
         Returns the rooms that a user is in.
 
         Args:
-            user_id(str): Must be a local user
+            user_id: Must be a local user
 
         Returns:
-            list: user_id
+            List of room IDs
         """
         rows = await self.db_pool.simple_select_onecol(
             table="users_who_share_private_rooms",
diff --git a/synapse/types.py b/synapse/types.py
index 773f0438d5..f2d436ddc3 100644
--- a/synapse/types.py
+++ b/synapse/types.py
@@ -143,8 +143,8 @@ class Requester:
         Requester.
 
         Args:
-            store (DataStore): Used to convert AS ID to AS object
-            input (dict): A dict produced by `serialize`
+            store: Used to convert AS ID to AS object
+            input: A dict produced by `serialize`
 
         Returns:
             Requester
diff --git a/synapse/util/async_helpers.py b/synapse/util/async_helpers.py
index 7f1d41eb3c..d24c4f68c4 100644
--- a/synapse/util/async_helpers.py
+++ b/synapse/util/async_helpers.py
@@ -217,7 +217,8 @@ async def concurrently_execute(
         limit: Maximum number of conccurent executions.
 
     Returns:
-        Deferred: Resolved when all function invocations have finished.
+        None, when all function invocations have finished. The return values
+        from those functions are discarded.
     """
     it = iter(args)
 
diff --git a/synapse/util/caches/__init__.py b/synapse/util/caches/__init__.py
index f7c3a6794e..9387632d0d 100644
--- a/synapse/util/caches/__init__.py
+++ b/synapse/util/caches/__init__.py
@@ -197,7 +197,7 @@ def register_cache(
         resize_callback: A function which can be called to resize the cache.
 
     Returns:
-        CacheMetric: an object which provides inc_{hits,misses,evictions} methods
+        an object which provides inc_{hits,misses,evictions} methods
     """
     if resizable:
         if not resize_callback:
diff --git a/synapse/util/caches/deferred_cache.py b/synapse/util/caches/deferred_cache.py
index bcb1cba362..bf7bd351e0 100644
--- a/synapse/util/caches/deferred_cache.py
+++ b/synapse/util/caches/deferred_cache.py
@@ -153,7 +153,7 @@ class DeferredCache(Generic[KT, VT]):
         Args:
             key:
             callback: Gets called when the entry in the cache is invalidated
-            update_metrics (bool): whether to update the cache hit rate metrics
+            update_metrics: whether to update the cache hit rate metrics
 
         Returns:
             A Deferred which completes with the result. Note that this may later fail
diff --git a/synapse/util/caches/dictionary_cache.py b/synapse/util/caches/dictionary_cache.py
index fa91479c97..5eaf70c7ab 100644
--- a/synapse/util/caches/dictionary_cache.py
+++ b/synapse/util/caches/dictionary_cache.py
@@ -169,10 +169,11 @@ class DictionaryCache(Generic[KT, DKT, DV]):
                 if it is in the cache.
 
         Returns:
-            DictionaryEntry: If `dict_keys` is not None then `DictionaryEntry`
-            will contain include the keys that are in the cache. If None then
-            will either return the full dict if in the cache, or the empty
-            dict (with `full` set to False) if it isn't.
+            If `dict_keys` is not None then `DictionaryEntry` will contain include
+            the keys that are in the cache.
+
+            If None then will either return the full dict if in the cache, or the
+            empty dict (with `full` set to False) if it isn't.
         """
         if dict_keys is None:
             # The caller wants the full set of dictionary keys for this cache key
diff --git a/synapse/util/caches/expiringcache.py b/synapse/util/caches/expiringcache.py
index c6a5d0dfc0..01ad02af67 100644
--- a/synapse/util/caches/expiringcache.py
+++ b/synapse/util/caches/expiringcache.py
@@ -207,7 +207,7 @@ class ExpiringCache(Generic[KT, VT]):
         items from the cache.
 
         Returns:
-            bool: Whether the cache changed size or not.
+            Whether the cache changed size or not.
         """
         new_size = int(self._original_max_size * factor)
         if new_size != self._max_size:
diff --git a/synapse/util/caches/lrucache.py b/synapse/util/caches/lrucache.py
index aa93109d13..dcf0eac3bf 100644
--- a/synapse/util/caches/lrucache.py
+++ b/synapse/util/caches/lrucache.py
@@ -389,11 +389,11 @@ class LruCache(Generic[KT, VT]):
             cache_name: The name of this cache, for the prometheus metrics. If unset,
                 no metrics will be reported on this cache.
 
-            cache_type (type):
+            cache_type:
                 type of underlying cache to be used. Typically one of dict
                 or TreeCache.
 
-            size_callback (func(V) -> int | None):
+            size_callback:
 
             metrics_collection_callback:
                 metrics collection callback. This is called early in the metrics
@@ -403,7 +403,7 @@ class LruCache(Generic[KT, VT]):
 
                 Ignored if cache_name is None.
 
-            apply_cache_factor_from_config (bool): If true, `max_size` will be
+            apply_cache_factor_from_config: If true, `max_size` will be
                 multiplied by a cache factor derived from the homeserver config
 
             clock:
@@ -796,7 +796,7 @@ class LruCache(Generic[KT, VT]):
         items from the cache.
 
         Returns:
-            bool: Whether the cache changed size or not.
+            Whether the cache changed size or not.
         """
         if not self.apply_cache_factor_from_config:
             return False
diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py
index 9f64fed0d7..2aceb1a47f 100644
--- a/synapse/util/ratelimitutils.py
+++ b/synapse/util/ratelimitutils.py
@@ -183,7 +183,7 @@ class FederationRateLimiter:
                 # Handle request ...
 
         Args:
-            host (str): Origin of incoming request.
+            host: Origin of incoming request.
 
         Returns:
             context manager which returns a deferred.
diff --git a/synapse/util/threepids.py b/synapse/util/threepids.py
index 1e9c2faa64..54bc7589fd 100644
--- a/synapse/util/threepids.py
+++ b/synapse/util/threepids.py
@@ -48,7 +48,7 @@ async def check_3pid_allowed(
         registration: whether we want to bind the 3PID as part of registering a new user.
 
     Returns:
-        bool: whether the 3PID medium/address is allowed to be added to this HS
+        whether the 3PID medium/address is allowed to be added to this HS
     """
     if not await hs.get_password_auth_provider().is_3pid_allowed(
         medium, address, registration
diff --git a/synapse/util/wheel_timer.py b/synapse/util/wheel_timer.py
index 177e198e7e..b1ec7f4bd8 100644
--- a/synapse/util/wheel_timer.py
+++ b/synapse/util/wheel_timer.py
@@ -90,10 +90,10 @@ class WheelTimer(Generic[T]):
         """Fetch any objects that have timed out
 
         Args:
-            now (ms): Current time in msec
+            now: Current time in msec
 
         Returns:
-            list: List of objects that have timed out
+            List of objects that have timed out
         """
         now_key = int(now / self.bucket_size)