diff --git a/api/s5/swagger.yaml b/api/s5/swagger.yaml
index 39f3403..01263e6 100644
--- a/api/s5/swagger.yaml
+++ b/api/s5/swagger.yaml
@@ -839,7 +839,7 @@ components:
         BasicUploadResponse:
             type: object
             properties:
-                CID:
+                cid:
                     type: string
         UploadRequestTryFiles:
             type: array