diff --git a/API.md b/API.md
index 09e471e0..0b113bd2 100644
--- a/API.md
+++ b/API.md
@@ -327,6 +327,7 @@ Required parameters:
Optional parameters:
custom_thumb (str): The URL for the custom library thumbnail
+ custom_art (str): The URL for the custom library background art
keep_history (int): 0 or 1
Returns:
diff --git a/data/interfaces/default/edit_library.html b/data/interfaces/default/edit_library.html
index f8c3863a..8b36a332 100644
--- a/data/interfaces/default/edit_library.html
+++ b/data/interfaces/default/edit_library.html
@@ -40,13 +40,22 @@ DOCUMENTATION :: END