diff --git a/src/NodeList.php b/src/NodeList.php
index 5256852..5ada864 100644
--- a/src/NodeList.php
+++ b/src/NodeList.php
@@ -167,6 +167,7 @@ public function count()
     /**
      * ArrayAccess: offset exists
      *
+     * @param int $key
      * @return bool
      */
     public function offsetExists($key)
@@ -180,6 +181,7 @@ public function offsetExists($key)
     /**
      * ArrayAccess: get offset
      *
+     * @param int $key
      * @return mixed
      */
     public function offsetGet($key)