diff --git a/drafts/push_csapi.rst b/drafts/push_csapi.rst
index 5f8515f14..1cc0131e7 100644
--- a/drafts/push_csapi.rst
+++ b/drafts/push_csapi.rst
@@ -101,7 +101,8 @@ rules of the same kind on different devices.
 A home server may also have server default rules of each kind and in each scope.
 Server default rules are lower priority than user-defined rules in eacgh scope.
 Server defined rules do not have a rule_id except when it is necessary to derive
-the function of the rule (ie. in room and sender rules).
+the function of the rule (ie. in room and sender rules). Server default rules
+have an attribute, "default" set to true.
 
 Push Rules: Actions:
 --------------------