diff --git a/framework/validators/StringValidator.php b/framework/validators/StringValidator.php
index 5a0fc3a..4d1b92c 100644
--- a/framework/validators/StringValidator.php
+++ b/framework/validators/StringValidator.php
@@ -159,6 +159,9 @@ class StringValidator extends Validator
         return 'yii.validation.string(value, messages, ' . json_encode($options, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE) . ');';
     }
 
+    /**
+     * @inheritdoc
+     */
     public function getClientOptions($model, $attribute)
     {
         $label = $model->getAttributeLabel($attribute);
diff --git a/framework/validators/Validator.php b/framework/validators/Validator.php
index 2915d31..3fcc966 100644
--- a/framework/validators/Validator.php
+++ b/framework/validators/Validator.php
@@ -352,7 +352,7 @@ class Validator extends Component
      * @param string $attribute the name of the attribute to be validated.
      * @param \yii\web\View $view the view object that is going to be used to render views or view files
      * containing a model form with this validator applied.
-     * @return string the client-side validation script. Null if the validator does not support
+     * @return string|null the client-side validation script. Null if the validator does not support
      * client-side validation.
      * @see getClientOptions()
      * @see \yii\widgets\ActiveForm::enableClientValidation