diff --git a/vast_pipeline/pipeline/new_sources.py b/vast_pipeline/pipeline/new_sources.py
index e365d8e90..b05fd5ecb 100644
--- a/vast_pipeline/pipeline/new_sources.py
+++ b/vast_pipeline/pipeline/new_sources.py
@@ -21,7 +21,7 @@
 logger = logging.getLogger(__name__)
 
 
-def check_primary_image(row) -> bool:
+def check_primary_image(row: pd.Series) -> bool:
     """
     Checks if the primary image is in the image list.