diff --git a/core/includes/ajax.inc b/core/includes/ajax.inc
index e52e4f3..b2f175a 100644
--- a/core/includes/ajax.inc
+++ b/core/includes/ajax.inc
@@ -187,11 +187,8 @@
  *
  * As developer you basically create a \Drupal\Core\Ajax\AjaxResponse and add
  * a couple of \Drupal\Core\Ajax\CommandInterface onto it, which will be
- * converted to a commands array automatically.
- *
- * When responding to Ajax requests, the server should do what it needs to do
- * for that request, then create a commands array. This commands array will
- * be converted to a JSON object and returned to the client, which will then
+ * converted to a commands array automatically. This commands array will be
+ * converted to a JSON object and returned to the client, which will then
  * iterate over the array and process it like a macro language.
  *
  * Each command item is an associative array which will be converted to a
diff --git a/core/lib/Drupal/Core/Ajax/AjaxResponseRenderer.php b/core/lib/Drupal/Core/Ajax/AjaxResponseRenderer.php
index f3e44da..6007e69 100644
--- a/core/lib/Drupal/Core/Ajax/AjaxResponseRenderer.php
+++ b/core/lib/Drupal/Core/Ajax/AjaxResponseRenderer.php
@@ -16,10 +16,10 @@
 class AjaxResponseRenderer {
 
   /**
-   * Converts a controller result into an Ajax response object.
+   * Converts the output of a a controller into an Ajax response object.
    *
    * @var mixed $content
-   *   The result of a controller, so for example a string, a render array, a
+   *   The return value of a controller, for example a string, a render array, a
    *   HtmlFragment object, a Response object or even an AjaxResponse itself.
    *
    * @return \Drupal\Core\Ajax\AjaxResponse
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
index d2c5c00..fff0ace 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
@@ -1668,7 +1668,7 @@ protected function drupalProcessAjaxResponse($content, array $ajax_response, arr
           // @todo Ajax commands can target any jQuery selector, but these are
           //   hard to fully emulate with XPath. For now, just handle 'head'
           //   and 'body', since these are used by
-          // \Drupal\Core\Ajax\AjaxResponse::ajaxRender().
+          //   \Drupal\Core\Ajax\AjaxResponse::ajaxRender().
           elseif (in_array($command['selector'], array('head', 'body'))) {
             $wrapperNode = $xpath->query('//' . $command['selector'])->item(0);
           }