diff --git a/core/lib/Drupal/Core/Template/TwigExtension.php b/core/lib/Drupal/Core/Template/TwigExtension.php
index 1a75a9a6ac9..13f97e58f4e 100644
--- a/core/lib/Drupal/Core/Template/TwigExtension.php
+++ b/core/lib/Drupal/Core/Template/TwigExtension.php
@@ -183,7 +183,7 @@ class TwigExtension extends AbstractExtension {
    * @param $name
    *   The name of the route.
    * @param array $parameters
-   *   An associative array of route parameters names and values.
+   *   (optional) An associative array of route parameters names and values.
    * @param array $options
    *   (optional) An associative array of additional options. The 'absolute'
    *   option is forced to be FALSE.