fix(proxy): always strip client guardrail info and mirror failure attribution into litellm_metadata

Backport of #59 to rc/1.105.0.
Cherry-picked from 79e48b9b19 (main). This line has no client pricing strip on pass-through, so only the guardrail strip is ported there.

litellm/proxy/litellm_pre_call_utils.py

@@ -367,10 +367,7 @@ _ALLOW_CLIENT_MESSAGE_REDACTION_OPT_OUT_METADATA_KEY: Final = "allow_client_mess
 _CLIENT_PRICING_CONTROL_FIELDS: Final = frozenset(CustomPricingLiteLLMParams.model_fields.keys()) | {"base_model"}
 # ``model_info`` carries the same pricing fields when read by
 # ``use_custom_pricing_for_model``; strip from metadata for the same reason.
-# ``standard_logging_guardrail_information`` is proxy-written telemetry summed
-# into response_cost and spend; a client seeding it forges (even negative)
-# guardrail cost.
-_CLIENT_PRICING_METADATA_FIELDS: Final = frozenset({"model_info", "standard_logging_guardrail_information"})
+_CLIENT_PRICING_METADATA_FIELDS: Final = frozenset({"model_info"})
 # ``attempted_fallbacks`` and ``original_model_group`` are written by the router
 # and read by spend logs as fact; a client value has no legitimate meaning and no
 # key or team setting keeps it, so the strip is never gated.
@@ -626,6 +623,19 @@ def _strip_client_pricing_overrides(data: dict[str, object]) -> None:
         )
 
 
+def strip_client_guardrail_information(data: dict[str, object]) -> None:
+    """Guardrail hooks write this field and its cost is billed, so no key or team setting keeps a caller's value."""
+    for metadata_key in ("metadata", "litellm_metadata"):
+        if (
+            isinstance(metadata := data.get(metadata_key), dict)
+            and "standard_logging_guardrail_information" in metadata
+        ):
+            metadata.pop("standard_logging_guardrail_information")
+            verbose_proxy_logger.debug(
+                "Stripped client-supplied guardrail information from request body: %s", metadata_key
+            )
+
+
 def _strip_router_reserved_metadata(
     data: dict[str, Any],  # mutable-ok: strips in place on the request body the pre-call pipeline threads through
 ) -> None:
@@ -2239,6 +2249,7 @@ async def add_litellm_data_to_request(
     # would silently skip the field.
     if not _key_or_team_allows_client_pricing_override(user_api_key_dict):
         _strip_client_pricing_overrides(data)
+    strip_client_guardrail_information(data)
     _strip_router_reserved_metadata(data)
 
     # Same reason as the strips above: runs after the metadata string-to-dict parse

litellm/proxy/pass_through_endpoints/pass_through_endpoints.py

@@ -102,6 +102,7 @@ from litellm.proxy.common_utils.sse_keepalive import (
 from litellm.proxy.litellm_pre_call_utils import (
     LiteLLMProxyRequestSetup,
     _get_dynamic_logging_metadata,  # pyright: ignore[reportPrivateUsage]  # shared proxy helper, same import style as _read_request_body above
+    strip_client_guardrail_information,
 )
 from litellm.proxy.route_llm_request import ProxyModelNotFoundError
 from litellm.proxy.utils import normalize_route_for_root_path
@@ -1133,6 +1134,9 @@ async def pass_through_request(
             _parsed_body,
         )
 
+        if _parsed_body is not None:
+            strip_client_guardrail_information(_parsed_body)
+
         ### COLLECT GUARDRAILS FOR PASSTHROUGH ENDPOINT ###
         # Passthrough endpoints are opt-in only for guardrails
         # When enabled, collect guardrails from org/team/key levels + passthrough-specific

litellm/proxy/utils.py

@@ -3738,6 +3738,7 @@ class ProxyLogging:
                     key: {
                         **_as_str_mapping(existing.get(key)),
                         **_as_str_mapping(value),
+                        **user_api_key_logged_metadata,
                     }
                     for key, value in _litellm_params.items()
                     if key == "litellm_metadata"

tests/unit/proxy/pass_through_endpoints/test_pass_through_endpoints.py

@@ -1343,6 +1343,39 @@ async def test_pass_through_request_uses_resolved_timeout():
             assert mock_get_client.call_args[1]["params"]["timeout"] == 1500
 
 
+@pytest.mark.asyncio
+@pytest.mark.parametrize("allow_client_pricing_override", [True, False])
+async def test_pass_through_request_strips_client_guardrail_information(allow_client_pricing_override: bool):
+    mock_request = MagicMock(spec=Request)
+    mock_request.method = "POST"
+    mock_request.headers = Headers({})
+    mock_request.query_params = QueryParams({})
+
+    with patch("litellm.proxy.proxy_server.proxy_logging_obj") as mock_proxy_logging:
+        mock_proxy_logging.pre_call_hook = AsyncMock(side_effect=RuntimeError("stop before upstream"))
+        mock_proxy_logging.post_call_failure_hook = AsyncMock()
+        with pytest.raises(ProxyException):
+            await pass_through_request(
+                request=mock_request,
+                target="http://test.com",
+                custom_headers={},
+                user_api_key_dict=UserAPIKeyAuth(
+                    metadata={"allow_client_pricing_override": allow_client_pricing_override}
+                ),
+                custom_body={
+                    "model": "gpt-4o",
+                    "input_cost_per_token": 0.5,
+                    "metadata": {
+                        "trace_id": "keep-me",
+                        "standard_logging_guardrail_information": [{"guardrail_name": "forged", "guardrail_cost": 5.0}],
+                    },
+                },
+            )
+
+    hooked_body: Final = mock_proxy_logging.pre_call_hook.call_args.kwargs["data"]
+    assert hooked_body["metadata"] == {"trace_id": "keep-me"}
+
+
 @pytest.mark.asyncio
 async def test_create_pass_through_route_forwards_timeout():
     unique_path = "/test/path/unique/timeout"

tests/unit/proxy/test_pricing_field_strip.py

@@ -22,6 +22,7 @@ from litellm.proxy.litellm_pre_call_utils import (
     _CLIENT_PRICING_METADATA_FIELDS,
     _strip_client_pricing_overrides,
     add_litellm_data_to_request,
+    strip_client_guardrail_information,
 )
 from litellm.types.utils import CustomPricingLiteLLMParams
 
@@ -136,7 +137,7 @@ class TestStripClientPricingOverrides:
                 "standard_logging_guardrail_information": [{"guardrail_cost": 5.0}],
             },
         }
-        _strip_client_pricing_overrides(data)
+        strip_client_guardrail_information(data)
         assert data["metadata"] == {"user_session": "keep-me"}
         assert data["litellm_metadata"] == {}
 
@@ -167,7 +168,6 @@ class TestStripClientPricingOverrides:
 
     def test_metadata_field_set_contains_model_info(self):
         assert "model_info" in _CLIENT_PRICING_METADATA_FIELDS
-        assert "standard_logging_guardrail_information" in _CLIENT_PRICING_METADATA_FIELDS
 
     def test_strip_emits_debug_log_listing_dropped_fields(self, caplog):
         # Operators need a paper trail so they can diagnose why a previously
@@ -300,6 +300,33 @@ async def test_add_litellm_data_to_request_skips_strip_with_key_opt_in():
     assert updated["base_model"] == "gpt-4o-mini"
 
 
+@pytest.mark.asyncio
+@pytest.mark.parametrize("opt_in_field", ["metadata", "team_metadata"])
+async def test_add_litellm_data_to_request_strips_guardrail_information_despite_pricing_opt_in(opt_in_field):
+    data = {
+        "model": "gpt-4",
+        "messages": [{"role": "user", "content": "hi"}],
+        "input_cost_per_token": 0.0001,
+        "metadata": {
+            "user_session": "keep-me",
+            "standard_logging_guardrail_information": [{"guardrail_name": "forged", "guardrail_cost": 5.0}],
+        },
+    }
+
+    updated = await add_litellm_data_to_request(
+        data=data,
+        request=_make_request_mock(),
+        user_api_key_dict=_user_api_key_auth(**{opt_in_field: {"allow_client_pricing_override": True}}),
+        proxy_config=MagicMock(),
+        general_settings={},
+        version="test-version",
+    )
+
+    assert updated["input_cost_per_token"] == 0.0001
+    assert updated["metadata"]["user_session"] == "keep-me"
+    assert "standard_logging_guardrail_information" not in updated["metadata"]
+
+
 @pytest.mark.asyncio
 async def test_add_litellm_data_to_request_strips_json_string_litellm_metadata():
     """``litellm_metadata`` may arrive as a JSON-encoded string (multipart/

tests/unit/proxy/test_proxy_utils_model_creation_and_error_logging.py

@@ -186,6 +186,7 @@ async def test_proxy_only_error_log_keeps_tags_and_drops_caller_logging_fields(
     assert "caller" not in str(details["litellm_params"])
     assert details["litellm_params"][metadata_field]["tags"] == ["t"]
     assert details["litellm_params"]["metadata"]["user_api_key_team_id"] == "team-a"
+    assert details["litellm_params"][metadata_field]["user_api_key_team_id"] == "team-a"
 
 
 @pytest.mark.asyncio