diff --git a/private/compat/30.0/30.0.cil b/private/compat/30.0/30.0.cil
index 44044fb..83d83ff 100644
--- a/private/compat/30.0/30.0.cil
+++ b/private/compat/30.0/30.0.cil
@@ -21,6 +21,7 @@
 
 (typeattribute binder_in_vendor_violators)
 
+;; mapping information from ToT policy's types to 30.0 policy's types.
 (expandtypeattribute (DockObserver_service_30_0) true)
 (expandtypeattribute (IProxyService_service_30_0) true)
 (expandtypeattribute (accessibility_service_30_0) true)