diff --git a/lib/bemenu.h b/lib/bemenu.h
index 7d96d2c..35a94e5 100644
--- a/lib/bemenu.h
+++ b/lib/bemenu.h
@@ -222,6 +222,7 @@ int bmMenuRemoveItem(bmMenu *menu, bmItem *item);
  * Highlight item in menu by index.
  *
  * @param menu bmMenu instance from where to highlight item.
+ * @param index Index of item to highlight.
  * @return 1 on successful highlight, 0 on failure.
  */
 int bmMenuSetHighlightedIndex(bmMenu *menu, unsigned int index);
diff --git a/lib/menu.c b/lib/menu.c
index f0a8149..5f57ae8 100644
--- a/lib/menu.c
+++ b/lib/menu.c
@@ -269,6 +269,7 @@ int bmMenuRemoveItem(bmMenu *menu, bmItem *item)
  * Highlight item in menu by index.
  *
  * @param menu bmMenu instance from where to highlight item.
+ * @param index Index of item to highlight.
  * @return 1 on successful highlight, 0 on failure.
  */
 int bmMenuSetHighlightedIndex(bmMenu *menu, unsigned int index)