diff --git a/api/server-server/keys_query.yaml b/api/server-server/keys_query.yaml
index a1ea80fbe..c2800bc6a 100644
--- a/api/server-server/keys_query.yaml
+++ b/api/server-server/keys_query.yaml
@@ -41,8 +41,9 @@ paths:
           name: keyId
           type: string
           description: |-
-            The key ID to look up. If omitted or empty, all the server's keys
-            are to be queried for.
+            **Deprecated**. Servers should not use this parameter and instead
+            opt to return all keys, not just the requested one. The key ID to 
+            look up.
           required: false
           x-example: "ed25519:abc123"
         - in: query
diff --git a/api/server-server/keys_server.yaml b/api/server-server/keys_server.yaml
index 07a2c5302..8734f2edd 100644
--- a/api/server-server/keys_server.yaml
+++ b/api/server-server/keys_server.yaml
@@ -29,10 +29,7 @@ paths:
       description: |-
         Gets the homeserver's published TLS fingerprints and signing keys.
         The homeserver may have any number of active keys and may have a
-        number of old keys. Homeservers SHOULD return a single JSON object
-        listing all of its keys, regardless of the ``keyId`` path argument.
-        This is to reduce the number of round trips needed to discover the
-        relevant keys for a homeserver.
+        number of old keys.
 
         Intermediate notary servers should cache a response for half of its
         lifetime to avoid serving a stale response. Originating servers should
@@ -51,10 +48,12 @@ paths:
           name: keyId
           type: string
           description: |-
-            The key ID to look up. If omitted or empty, all server keys are
-            to be returned.
+            **Deprecated**. Servers should not use this parameter and instead
+            opt to return all keys, not just the requested one. The key ID to 
+            look up.
           required: false
           x-example: "ed25519:abc123"
+          deprecated: true
       responses:
         200:
           description: The homeserver's keys