diff --git a/backend.yml b/backend.yml
index 08f2ae8..86d1ea5 100644
--- a/backend.yml
+++ b/backend.yml
@@ -212,6 +212,9 @@ components:
         cover_url:
           type: string
           format: url
+        cover_url_small:
+          type: string
+          format: url
     LoginToken:
       required:
       - token