diff --git a/backend/packages/harness/deerflow/community/serper/tools.py b/backend/packages/harness/deerflow/community/serper/tools.py
index 005a3090e..9f960981d 100644
--- a/backend/packages/harness/deerflow/community/serper/tools.py
+++ b/backend/packages/harness/deerflow/community/serper/tools.py
@@ -149,7 +149,10 @@ def _safe_public_url(value: object) -> str:
     if not isinstance(value, str):
         return ""
     url = value.strip()
-    parsed = urlparse(url)
+    try:
+        parsed = urlparse(url)
+    except ValueError:
+        return ""
     if parsed.scheme not in {"http", "https"} or not parsed.netloc or not parsed.hostname:
         return ""
 
diff --git a/backend/tests/test_serper_tools.py b/backend/tests/test_serper_tools.py
index 7df5311ec..f1bbddc9d 100644
--- a/backend/tests/test_serper_tools.py
+++ b/backend/tests/test_serper_tools.py
@@ -269,6 +269,11 @@ class TestSafePublicUrl:
 
         assert _safe_public_url("http://[::ffff:127.0.0.1]/x.jpg") == ""
 
+    def test_malformed_ipv6_url_does_not_raise(self):
+        from deerflow.community.serper.tools import _safe_public_url
+
+        assert _safe_public_url("http://[::1/i.jpg") == ""
+
     def test_non_http_scheme_is_filtered(self):
         from deerflow.community.serper.tools import _safe_public_url