diff --git a/src/app/application.js b/src/app/application.js
index afccadab85..7783f1a976 100644
--- a/src/app/application.js
+++ b/src/app/application.js
@@ -98,7 +98,7 @@ export class AppOptions {
   /**
    * Tool name indexed object containing individual tool configurations.
    *
-   * @type {Object<string, ToolConfig>}
+   * @type {Object<string, ToolConfig>|undefined}
    */
   tools;
   /**