diff --git a/openeo_driver/views.py b/openeo_driver/views.py
index 5700f465..b5978f5d 100644
--- a/openeo_driver/views.py
+++ b/openeo_driver/views.py
@@ -1743,7 +1743,7 @@ def _get_job_result_item(job_id, item_id, user_id):
         }
 
         if len(assets_for_item_id) != 1:
-            raise AssertionError(f"expected exactly 1 asset with file name {item_id}")
+            raise AssertionError(f"expected exactly 1 asset with file name {item_id}. Got {len(assets_for_item_id)}")
 
         asset_filename, asset_metadata = next(iter(assets_for_item_id.items()))