diff --git a/core/lib/Drupal/Core/Template/Loader/StringLoader.php b/core/lib/Drupal/Core/Template/Loader/StringLoader.php
index c1c23a3..c943ac6 100644
--- a/core/lib/Drupal/Core/Template/Loader/StringLoader.php
+++ b/core/lib/Drupal/Core/Template/Loader/StringLoader.php
@@ -7,13 +7,21 @@
 
 namespace Drupal\Core\Template\Loader;
 
+/**
+ * Loads string templates, also known as inline templates.
+ *
+ * We only allow strings that begin with a specific comment so that exceptions
+ * are thrown when a template does not exist.
+ *
+ * @see \Drupal\Core\Template\TwigEnvironment::renderInline()
+ * @see \Drupal\Core\Render\Element\InlineTemplate
+ */
 class StringLoader extends \Twig_Loader_String {
 
   /**
    * {@inheritdoc}
    */
   public function exists($name) {
-    // See \Drupal\Core\Template\TwigEnvironment::renderInline().
     if (strpos($name, '{# inline_template_start #}') === 0) {
       return TRUE;
     }