fix(model_armor): record logging_only verdicts without raising so both scans run

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

litellm/proxy/guardrails/guardrail_hooks/model_armor/model_armor.py

@@ -1245,7 +1245,7 @@ class ModelArmorGuardrail(CustomGuardrail, VertexBase):
             armor_response: Final = await self.make_model_armor_request(
                 content=content, source=source, request_data=request_data
             )
-        except ModelArmorAPIError as e:
+        except (ModelArmorAPIError, httpx.HTTPError) as e:
             error_end_time: Final = time.time()
             self.add_standard_logging_guardrail_information_to_request_data(
                 guardrail_json_response=str(e),
@@ -1256,7 +1256,7 @@ class ModelArmorGuardrail(CustomGuardrail, VertexBase):
                 end_time=error_end_time,
                 duration=error_end_time - start_time,
             )
-            raise
+            return inputs
 
         flagged: Final = self._should_block_content(armor_response, allow_sanitization=False)
         end_time: Final = time.time()
@@ -1269,14 +1269,6 @@ class ModelArmorGuardrail(CustomGuardrail, VertexBase):
             end_time=end_time,
             duration=end_time - start_time,
         )
-        if flagged:
-            raise HTTPException(
-                status_code=400,
-                detail=self._build_block_error_detail(
-                    "Response blocked by Model Armor" if input_type == "response" else "Violated content safety policy",
-                    armor_response,
-                ),
-            )
         return inputs
 
     @staticmethod

tests/test_litellm/proxy/guardrails/guardrail_hooks/test_model_armor.py

@@ -5203,18 +5203,55 @@ async def test_native_post_call_mode_ignores_logging_hook():
 
 
 @pytest.mark.asyncio
-async def test_apply_guardrail_raises_on_flagged_content():
+async def test_apply_guardrail_records_flagged_without_raising():
     guardrail = _logging_only_guardrail()
     guardrail.make_model_armor_request = AsyncMock(return_value=_flagged_armor_response())
     request_data = {"metadata": {}}
+    inputs = {"texts": ["forbidden output"]}
 
-    with pytest.raises(HTTPException) as exc_info:
-        await guardrail.apply_guardrail(
-            inputs={"texts": ["forbidden output"]},
-            request_data=request_data,
-            input_type="response",
-        )
+    result = await guardrail.apply_guardrail(
+        inputs=inputs,
+        request_data=request_data,
+        input_type="response",
+    )
 
-    assert exc_info.value.status_code == 400
+    assert result == inputs
     entries = request_data["metadata"]["standard_logging_guardrail_information"]
     assert entries[-1]["guardrail_status"] == "guardrail_flagged"
+
+
+@pytest.mark.asyncio
+async def test_logging_only_records_transport_error():
+    guardrail = _logging_only_guardrail()
+    guardrail.make_model_armor_request = AsyncMock(side_effect=httpx.ConnectError("boom"))
+    response = _chat_response("some output")
+    kwargs = _logged_kwargs()
+
+    out_kwargs, out_result = await guardrail.async_logging_hook(
+        kwargs=kwargs, result=response, call_type="acompletion"
+    )
+
+    assert out_result is response
+    entries = _metadata_entries(out_kwargs)
+    failed = [e for e in entries if e["guardrail_status"] == "guardrail_failed_to_respond"]
+    assert failed
+    assert all(e["guardrail_provider"] == "model_armor" for e in failed)
+
+
+@pytest.mark.asyncio
+async def test_logging_only_flagged_prompt_still_scans_response():
+    """A flagged input scan must not abort the output scan; both verdicts are recorded."""
+    guardrail = _logging_only_guardrail()
+    guardrail.make_model_armor_request = AsyncMock(return_value=_flagged_armor_response())
+    response = _chat_response("flagged output")
+    kwargs = _logged_kwargs()
+
+    out_kwargs, _ = await guardrail.async_logging_hook(
+        kwargs=kwargs, result=response, call_type="acompletion"
+    )
+
+    sources = [call.kwargs.get("source") for call in guardrail.make_model_armor_request.await_args_list]
+    assert sources == ["user_prompt", "model_response"]
+    entries = _metadata_entries(out_kwargs)
+    flagged = [e for e in entries if e["guardrail_status"] == "guardrail_flagged"]
+    assert len(flagged) == 2