diff --git a/README.md b/README.md
index 6fc5bd2..4ad39ca 100644
--- a/README.md
+++ b/README.md
@@ -199,3 +199,7 @@ Run the tests with
 Lint with
 
     composer lint
+    
+The project parses PHPStorm's PHP stubs to get support for PHP builtins. It re-parses them as needed after Composer processes, but after some code changes (such as ones involving the index or parsing) you may have to explicitly re-parse them:
+
+    composer run-script parse-stubs