diff --git a/src/github.com/matrix-org/dendrite/roomserver/api/query.go b/src/github.com/matrix-org/dendrite/roomserver/api/query.go
index b47184c8..6f26212d 100644
--- a/src/github.com/matrix-org/dendrite/roomserver/api/query.go
+++ b/src/github.com/matrix-org/dendrite/roomserver/api/query.go
@@ -41,6 +41,7 @@ type QueryLatestEventsAndStateResponse struct {
 	// The latest events in the room.
 	LatestEvents []gomatrixserverlib.EventReference
 	// The state events requested.
+	// This list will be in an arbitrary order.
 	StateEvents []gomatrixserverlib.Event
 }
 
@@ -65,6 +66,7 @@ type QueryStateAfterEventsResponse struct {
 	// If some of previous events do not exist this will be false and StateEvents will be empty.
 	PrevEventsExist bool
 	// The state events requested.
+	// This list will be in an arbitrary order.
 	StateEvents []gomatrixserverlib.Event
 }
 
@@ -78,9 +80,13 @@ type QueryEventsByIDRequest struct {
 type QueryEventsByIDResponse struct {
 	// Copy of the request for debugging.
 	QueryEventsByIDRequest
-	// A list of events with the request IDs.
+	// A list of events with the requested IDs.
 	// If the roomserver does not have a copy of a requested event
 	// then it will omit that event from the list.
+	// If the roomserver thinks it has a copy of the event, but
+	// fails to read it from the database then it will fail
+	// the entire request.
+	// This list will be in an arbitrary order.
 	Events []gomatrixserverlib.Event
 }