diff --git a/synapse/state.py b/synapse/state.py
index 2f6eea09aa77c84c2f364c7862c1b2f2bedf8750..38adde4dc9f03e2b7c6f34d2b46bb133d8e4bc6a 100644
--- a/synapse/state.py
+++ b/synapse/state.py
@@ -138,8 +138,8 @@ class StateHandler(object):
     @defer.inlineCallbacks
     def annotate_context_with_state(self, event, context, old_state=None):
         """ Fills out the context with the `current state` of the graph. The
-        `current state` here is defined to be exclusive of the given event,
-        i.e. its the state of the event graph just before the event.
+        `current state` here is defined to be the state of the event graph
+        just before the event - i.e. it never includes `event`
 
         If `event` has `auth_events` then this will also fill out the
         `auth_events` field on `context` from the `current_state`.