diff --git a/core/modules/system/tests/modules/ajax_test/src/Controller/AjaxTestController.php b/core/modules/system/tests/modules/ajax_test/src/Controller/AjaxTestController.php
index fc85b2c..483e696 100644
--- a/core/modules/system/tests/modules/ajax_test/src/Controller/AjaxTestController.php
+++ b/core/modules/system/tests/modules/ajax_test/src/Controller/AjaxTestController.php
@@ -20,6 +20,9 @@ class AjaxTestController {
 
   /**
    * Returns example content for dialog testing.
+   *
+   * @return array
+   *   The render array.
    */
   public function dialogContents() {
     // Re-use the utility method that returns the example content.
@@ -28,11 +31,14 @@ public function dialogContents() {
   }
 
   /**
-   *Returns an element suitable for use by
+   * Returns an element suitable for use by
    * \Drupal\Core\Ajax\AjaxResponse::ajaxRender().
    * Additionally ensures that \Drupal\Core\Ajax\AjaxResponse::ajaxRender()
    * incorporates JavaScript settings generated during the page request by
    * invoking _drupal_add_js() with a dummy setting.
+   *
+   * @return \Drupal\Core\Ajax\AjaxResponse $response
+   *   The JSON response object.
    */
   public function render() {
     $attached = array(
@@ -52,6 +58,9 @@ public function render() {
   /**
    * Returns an AjaxResponse; settings command set last.
    * Helps verifying AjaxResponse reorders commands to ensure correct execution.
+   *
+   * @return \Drupal\Core\Ajax\AjaxResponse $response
+   *   The JSON response object.
    */
   public function order() {
     $response = new AjaxResponse();
@@ -65,6 +74,9 @@ public function order() {
 
   /**
    * Menu callback: Returns AJAX element with #error property set.
+   *
+   * @return \Drupal\Core\Ajax\AjaxResponse $response
+   *   The JSON response object.
    */
   public function renderError() {
     $message = '';
@@ -78,7 +90,10 @@ public function renderError() {
   }
 
   /**
+   *  Returns the render array for the links.
    *
+   * @return array
+   *   The render array.
    */
   public function dialog() {
     // Add two wrapper elements for testing non-modal dialogs. Modal dialogs use
@@ -172,6 +187,9 @@ public function dialog() {
 
   /**
    * Close the ajax dialog.
+   *
+   * @return \Drupal\Core\Ajax\AjaxResponse $response
+   *   The JSON response object.
    */
   public function dialogClose() {
     $response = new AjaxResponse();