diff --git a/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php b/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php
index 2547e27..996dd5f 100644
--- a/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php
+++ b/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php
@@ -9,10 +9,13 @@
 
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Plugin\Discovery\ContainerDerivativeInterface;
+use Drupal\Component\Plugin\Exception\PluginException;
 use Drupal\Core\StringTranslation\TranslationManager;
-use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Component\Utility\String;
 use Drupal\Component\Discovery\YamlDiscovery;
 
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
 /**
  * Provides plugin derivatives for local actions provided in YAML files.
  */
@@ -89,11 +92,17 @@ public function getDerivativeDefinition($derivative_id, array $base_plugin_defin
    */
   public function getDerivativeDefinitions(array $base_plugin_definition) {
     $yaml_discovery = new YamlDiscovery('local_actions', $this->moduleHandler->getModuleDirectories());
+    $required_keys = array('title' => 1, 'route_name' => 1, 'appears_on' => 1);
 
     foreach ($yaml_discovery->findAll() as $module => $local_actions) {
       if (!empty($local_actions)) {
         foreach ($local_actions as $name => $info) {
-          $info += array('title' => '', 'provider' => $module);
+          if ($missing_keys = array_diff_key($required_keys, array_intersect_key($info, $required_keys))) {
+            throw new PluginException(String::format('Static local action @name is missing @keys', array('@name' => $name, '@keys' => implode(', ', array_keys($missing_keys)))));
+          }
+          $info += array('provider' => $module, 'appears_on' => array());
+          // Make sure 'appears_on' is an array.
+          $info['appears_on'] = (array) $info['appears_on'];
           $info['title'] = $this->translationManager->translate($info['title']);
           $this->derivatives[$name] = $info + $base_plugin_definition;
         }