--- a/testing/marionette/components/marionette.js
+++ b/testing/marionette/components/marionette.js
@@ -143,22 +143,25 @@ function MarionetteComponent() {
     Preferences.set(PREF_ENABLED, Preferences.get(PREF_ENABLED_FALLBACK));
   }
 }
 
 MarionetteComponent.prototype = {
   classDescription: "Marionette component",
   classID: MARIONETTE_CID,
   contractID: MARIONETTE_CONTRACT_ID,
-  QueryInterface: XPCOMUtils.generateQI(
-      [Ci.nsICommandLineHandler, Ci.nsIObserver]),
+  QueryInterface: XPCOMUtils.generateQI([
+    Ci.nsICommandLineHandler,
+    Ci.nsIObserver,
+  ]),
   _xpcom_categories: [
     {category: "command-line-handler", entry: "b-marionette"},
     {category: "profile-after-change", service: true},
   ],
+  helpInfo: "  --marionette       Enable remote control server.\n",
 };
 
 MarionetteComponent.prototype.onSocketAccepted = function (socket, transport) {
   this.logger.info("onSocketAccepted for Marionette dummy socket");
 };
 
 MarionetteComponent.prototype.onStopListening = function (socket, status) {
   this.logger.info(`onStopListening for Marionette dummy socket, code ${status}`);