diff --git a/synapse/replication/http/membership.py b/synapse/replication/http/membership.py
index 98ab24f24d7c..7631a7f280b6 100644
--- a/synapse/replication/http/membership.py
+++ b/synapse/replication/http/membership.py
@@ -115,17 +115,11 @@ def __init__(self, hs):
 
     @staticmethod
     async def _serialize_payload(  # type: ignore
-        requester: Requester,
-        room_id: str,
-        user_id: str,
-        remote_room_hosts: List[str],
-        content: JsonDict,
+        requester: Requester, remote_room_hosts: List[str], content: JsonDict,
     ):
         """
         Args:
             requester: The user making the request, according to the access token.
-            room_id: The ID of the room to knock on.
-            user_id: The ID of the knocking user.
             remote_room_hosts: Servers to try and send the knock via.
             content: The event content to use for the knock event.
         """
@@ -245,14 +239,10 @@ def __init__(self, hs: "HomeServer"):
 
     @staticmethod
     async def _serialize_payload(  # type: ignore
-        knock_event_id: str,
-        txn_id: Optional[str],
-        requester: Requester,
-        content: JsonDict,
+        txn_id: Optional[str], requester: Requester, content: JsonDict,
     ):
         """
         Args:
-            knock_event_id: The ID of the knock to be rescinded.
             txn_id: An optional transaction ID supplied by the client.
             requester: The user making the rescind request, according to the access token.
             content: The content to include in the rescind event.