diff --git a/include/items.php b/include/items.php
index a4d8d8ef1..cb80ce851 100644
--- a/include/items.php
+++ b/include/items.php
@@ -359,6 +359,7 @@ function item_add_language_opt(&$arr) {
  * @brief Creates an unique guid out of a given uri
  *
  * @param string $uri uri of an item entry
+ * @param string $host (Optional) hostname for the GUID prefix
  * @return string unique guid
  */
 function uri_to_guid($uri, $host = "") {