diff -u b/core/lib/Drupal/Component/Plugin/ConfigurablePluginInterface.php b/core/lib/Drupal/Component/Plugin/ConfigurablePluginInterface.php
--- b/core/lib/Drupal/Component/Plugin/ConfigurablePluginInterface.php
+++ b/core/lib/Drupal/Component/Plugin/ConfigurablePluginInterface.php
@@ -39,8 +39,24 @@
   /**
    * Calculates dependencies.
    *
+   * Dependencies are saved in the plugin's configuration entity and are used to
+   * determine configuration synchronization order. For example, if the plugin
+   * integrates with specific user roles, this method should return an array of
+   * dependencies listing the specified roles.
+   *
    * @return array
-   *   An array of dependencies grouped by type (module, theme, entity).
+   *   An array of dependencies grouped by type (module, theme, entity). For
+   *   example:
+   *   @code
+   *   array(
+   *     'entity' => array('user.role.anonymous', 'user.role.authenticated'),
+   *     'module' => array('node', 'user'),
+   *     'theme' => array('seven'),
+   *   );
+   *   @endcode
+   *
+   * @see \Drupal\Core\Config\Entity\ConfigDependencyManager
+   * @see \Drupal\Core\Config\Entity\ConfigEntityInterface::getConfigDependencyName()
    */
   public function calculateDependencies();