diff --git a/backend/tests/AGENTS.md b/backend/tests/AGENTS.md
index 7c8c6b9e96..02653e71ae 100644
--- a/backend/tests/AGENTS.md
+++ b/backend/tests/AGENTS.md
@@ -1,5 +1,9 @@
 # Backend Tests
 
+`test_image_result_url_safety.py` drives GroundRoute through `ainvoke` and an
+offline HTTPX transport. Patch only the provider's `httpx` reference; preserve
+the shared client and exercise real configuration resolution and URL screening.
+
 `test_client_upload_snapshot.py` keeps upload publication and conversion on the
 same private capture. Cover source edits/removal, both conversion branches,
 same-file rejection, metadata and cleanup; retain sandbox symlink defenses.
diff --git a/backend/tests/test_image_result_url_safety.py b/backend/tests/test_image_result_url_safety.py
index 8522e9a51d..83308af8cb 100644
--- a/backend/tests/test_image_result_url_safety.py
+++ b/backend/tests/test_image_result_url_safety.py
@@ -95,7 +95,17 @@ def _stub_serply(module, url):
 
 def _stub_groundroute(module, url):
     data = {"results": [{"title": "t", "url": url, "snippet": "c"}]}
-    return [patch.object(module, "_get_api_key", return_value="k"), patch.object(module, "_post_search", return_value=data)], _sync(module.web_search_tool)
+    config = SimpleNamespace(get_tool_config=lambda _: SimpleNamespace(model_extra={"api_key": "synthetic-test-key"}))
+    transport = httpx.MockTransport(lambda request: httpx.Response(200, json=data))
+    real_client = httpx.AsyncClient
+    return [
+        patch.object(module, "get_app_config", return_value=config),
+        patch.object(
+            module,
+            "httpx",
+            SimpleNamespace(AsyncClient=lambda **kwargs: real_client(transport=transport, **kwargs), HTTPStatusError=httpx.HTTPStatusError),
+        ),
+    ], _async(module.web_search_tool)
 
 
 def _stub_sofya(module, url):