diff --git a/core/modules/simpletest/simpletest.info.yml b/core/modules/simpletest/simpletest.info.yml
index 232680e..415817a 100644
--- a/core/modules/simpletest/simpletest.info.yml
+++ b/core/modules/simpletest/simpletest.info.yml
@@ -1,6 +1,6 @@
 name: Testing
 type: module
-description: 'Provides a framework for unit and functional testing.'
+description: 'Provides a framework for unit and functional testing. Requires the PHP cURL library to be installed on the server.'
 package: Core
 version: VERSION
 core: 8.x
diff --git a/core/modules/simpletest/simpletest.module b/core/modules/simpletest/simpletest.module
index 3b46028..e03cee7 100644
--- a/core/modules/simpletest/simpletest.module
+++ b/core/modules/simpletest/simpletest.module
@@ -29,6 +29,8 @@ function simpletest_help($route_name, RouteMatchInterface $route_match) {
       $output .= '<dd><p>' . t('Visit the <a href="!admin-simpletest">Testing page</a> to display a list of available tests. For comprehensive testing, select <em>all</em> tests, or individually select tests for more targeted testing. Note that it might take several minutes for all tests to complete.', array('!admin-simpletest' => \Drupal::url('simpletest.test_form'))) . '</p>';
       $output .= '<p>' . t('After the tests run, a message will be displayed next to each test group indicating whether tests within it passed, failed, or had exceptions. A pass means that the test returned the expected results, while fail means that it did not. An exception normally indicates an error outside of the test, such as a PHP warning or notice. If there were failures or exceptions, the results will be expanded to show details, and the tests that had failures or exceptions will be indicated in red or pink rows. You can then use these results to refine your code and tests, until all tests pass.') . '</p></dd>';
       $output .= '</dl>';
+      $output .= '<h3>' . t('Requirements') . '</h3>';
+      $output .= '<p>' . t('The PHP <a href="@curl_url">cURL</a> library needs to be installed on the server. You should check the cURL status via phpinfo(). On Unix, you have to install the php5-curl library. On Windows XAMPP, you have to enable the cURL extension by removing the ";" before "extension=php_curl.dll". Apache must be restarted after applying changes to the server.', array('@curl_url' => 'http://php.net/manual/curl.setup.php')) . '</p>';
       return $output;
 
     case 'simpletest.test_form':