diff --git a/Urbit/Airlock.hs b/Urbit/Airlock.hs
index d7f2757..ef1a853 100644
--- a/Urbit/Airlock.hs
+++ b/Urbit/Airlock.hs
@@ -116,6 +116,7 @@ poke ::
   Text ->
   -- | The mark of the message you are sending
   Text ->
+  -- | The actual JSON message, serialized via aeson
   a ->
   IO Req.BsResponse
 poke sess ship shipName app mark json =