diff --git a/web/src/pages/chat/markdown-content/index.tsx b/web/src/pages/chat/markdown-content/index.tsx
index 02ec95a6b..cd0ce3586 100644
--- a/web/src/pages/chat/markdown-content/index.tsx
+++ b/web/src/pages/chat/markdown-content/index.tsx
@@ -54,7 +54,8 @@ const MarkdownContent = ({
   }, [content, loading, t]);
 
   useEffect(() => {
-    setDocumentIds(reference?.doc_aggs?.map((x) => x.doc_id) ?? []);
+    const docAggs = reference?.doc_aggs;
+    setDocumentIds(Array.isArray(docAggs) ? docAggs.map((x) => x.doc_id) : []);
   }, [reference, setDocumentIds]);
 
   const handleDocumentButtonClick = useCallback(