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diff --git a/include/grpc/grpc.h b/include/grpc/grpc.h
index 153c74b..2821c9e 100644
--- a/include/grpc/grpc.h
+++ b/include/grpc/grpc.h
@@ -517,7 +517,9 @@
 void grpc_server_cancel_all_calls(grpc_server *server);
 
 /* Destroy a server.
-   Shutdown must have completed beforehand. */
+   Shutdown must have completed beforehand (i.e. all tags generated by
+   grpc_server_shutdown_and_notify must have been received, and at least
+   one call to grpc_server_shutdown_and_notify must have been made). */
 void grpc_server_destroy(grpc_server *server);
 
 #ifdef __cplusplus