diff --git a/changelog.d/6775.doc b/changelog.d/6775.doc
new file mode 100644
index 0000000000000000000000000000000000000000..9421250f8be1c09bcf947f92778b2483c4c05c92
--- /dev/null
+++ b/changelog.d/6775.doc
@@ -0,0 +1 @@
+Clarify documentation related to user_dir and federation_reader workers.
diff --git a/docs/workers.md b/docs/workers.md
index 0ab269fd96bb5a7ff85c985ec4069686a1d28e51..a5d6d18f2313a8bfb8e5736d5215e4c4888b3132 100644
--- a/docs/workers.md
+++ b/docs/workers.md
@@ -185,6 +185,9 @@ reverse-proxy configuration.
 The `^/_matrix/federation/v1/send/` endpoint must only be handled by a single
 instance.
 
+Note that the `worker_listeners.resources.name` needs to be set to `federation`
+for this worker.
+
 ### `synapse.app.federation_sender`
 
 Handles sending federation traffic to other servers. Doesn't handle any
@@ -265,6 +268,10 @@ the following regular expressions:
 
     ^/_matrix/client/(api/v1|r0|unstable)/user_directory/search$
 
+When using this worker you must also set `update_user_directory: False` in the 
+shared configuration file to stop the main synapse running background 
+jobs related to updating the user directory.
+
 ### `synapse.app.frontend_proxy`
 
 Proxies some frequently-requested client endpoints to add caching and remove