From 4f585d393147bf9f5cfc57bef5f973aa04c8ddbe Mon Sep 17 00:00:00 2001 From: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com> Date: Wed, 16 Sep 2026 18:35:49 +0000 Subject: [PATCH 1/2] fix(responses): drop top_p for gpt-5 reasoning models when drop_params is set Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com> --- .../llms/openai/responses/transformation.py | 29 +++++++++++--- ...bedrock_mantle_responses_transformation.py | 23 +++++++++++ .../test_openai_responses_transformation.py | 40 +++++++++++++++++++ 3 files changed, 86 insertions(+), 6 deletions(-) diff --git a/litellm/llms/openai/responses/transformation.py b/litellm/llms/openai/responses/transformation.py index 833ae206024..0d8d6934795 100644 --- a/litellm/llms/openai/responses/transformation.py +++ b/litellm/llms/openai/responses/transformation.py @@ -208,8 +208,9 @@ class OpenAIResponsesAPIConfig(BaseResponsesAPIConfig): ) -> dict: """No mapping applied since inputs are in OpenAI spec already. - GPT-5 models have restrictions on temperature (only temperature=1 - is accepted unless reasoning_effort='none' on models that support it). + GPT-5 models have restrictions on temperature and top_p (only temperature=1 + is accepted, and top_p is rejected, unless reasoning.effort resolves to + 'none' on models that support it). Apply the same validation used by the chat completions path. """ params: Final = dict(response_api_optional_params) @@ -235,12 +236,14 @@ class OpenAIResponsesAPIConfig(BaseResponsesAPIConfig): ) if self._is_gpt_5_model(model=model): + reasoning: Final = params.get("reasoning") or {} + effort: Final = reasoning.get("effort") if isinstance(reasoning, dict) else None + supports_none: Final = self._supports_reasoning_effort_none(model=model) + effort_is_none: Final = supports_none and self._effort_resolves_to_none(model, effort) + temperature: Final = params.get("temperature") if temperature is not None and temperature != 1: - reasoning: Final = params.get("reasoning") or {} - effort: Final = reasoning.get("effort") if isinstance(reasoning, dict) else None - supports_none: Final = self._supports_reasoning_effort_none(model=model) - if supports_none and self._effort_resolves_to_none(model, effort): + if effort_is_none: pass # flexible temperature allowed elif drop_params or litellm.drop_params: params.pop("temperature", None) @@ -256,6 +259,20 @@ class OpenAIResponsesAPIConfig(BaseResponsesAPIConfig): status_code=400, ) + if "top_p" in params and not effort_is_none: + if drop_params or litellm.drop_params: + params.pop("top_p", None) + else: + raise litellm.UnsupportedParamsError( + message=( + f"{model} only supports top_p when reasoning.effort resolves to 'none', " + "either set explicitly on the request or declared as the model's " + "default_reasoning_effort. " + "To drop unsupported params set `litellm.drop_params = True`" + ), + status_code=400, + ) + return params def transform_responses_api_request( diff --git a/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py b/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py index a7aefa714aa..afd284d31c8 100644 --- a/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py +++ b/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py @@ -369,6 +369,29 @@ class TestBedrockMantleResponsesTools: assert "file_search" in str(mock_warning.call_args) +class TestBedrockMantleSamplingParams: + """Mantle rejects top_p on its gpt-5 reasoning models and non-default temperature + while reasoning is active, the same rule the OpenAI Responses surface applies, so + drop_params must strip both before the request leaves.""" + + @pytest.mark.parametrize( + "model", + [ + "openai.gpt-5.4", + "openai.gpt-5.5", + "openai.gpt-5.6-luna", + ], + ) + def test_map_openai_params_drops_top_p_and_temperature(self, local_cost_map, model): + params = BedrockMantleResponsesAPIConfig().map_openai_params( + response_api_optional_params={"top_p": 0.9, "temperature": 0.2}, + model=model, + drop_params=True, + ) + assert "top_p" not in params + assert "temperature" not in params + + class TestBedrockMantleResponsesWebSearch: """Web Search on Amazon Bedrock is a server-side built-in tool that Mantle runs itself when the caller passes {"type": "web_search"} on the Responses path, so diff --git a/tests/test_litellm/llms/openai/responses/test_openai_responses_transformation.py b/tests/test_litellm/llms/openai/responses/test_openai_responses_transformation.py index 4cf8767764b..2bc8d74e82c 100644 --- a/tests/test_litellm/llms/openai/responses/test_openai_responses_transformation.py +++ b/tests/test_litellm/llms/openai/responses/test_openai_responses_transformation.py @@ -1835,6 +1835,46 @@ class TestResponsesSurfaceSharesTheEffortRule: ) assert ("temperature" in mapped) is temperature_survives + @pytest.mark.parametrize( + "model, effort, top_p_survives", + [ + ("gpt-5.1", None, True), + ("gpt-5.4", None, True), + ("gpt-5.5", None, False), + ("gpt-5.6-terra", None, False), + ("gpt-5.6-sol", None, False), + ("gpt-5.6-terra", "none", True), + ("gpt-5.6-terra", "medium", False), + ("gpt-6-astra", None, False), + ("gpt-6-astra", "low", False), + ], + ) + def test_top_p_follows_the_resolved_effort(self, local_model_cost_map, model, effort, top_p_survives): + params = {"top_p": 0.9} + if effort is not None: + params["reasoning"] = {"effort": effort} + mapped = OpenAIResponsesAPIConfig().map_openai_params( + response_api_optional_params=params, + model=model, + drop_params=True, + ) + assert ("top_p" in mapped) is top_p_survives + + def test_top_p_raises_without_drop_params(self, local_model_cost_map): + with pytest.raises(litellm.UnsupportedParamsError): + OpenAIResponsesAPIConfig().map_openai_params( + response_api_optional_params={"top_p": 0.9}, + model="gpt-5.5", + drop_params=False, + ) + + mapped = OpenAIResponsesAPIConfig().map_openai_params( + response_api_optional_params={"top_p": 0.9, "reasoning": {"effort": "none"}}, + model="gpt-5.6-terra", + drop_params=False, + ) + assert mapped["top_p"] == 0.9 + class TestFlattenToolSchemaCombinatorsWiring: """Regression tests for MCP tools with a top-level anyOf schema (Codex Desktop). From 9ae5bde829a7be855ed8ca6f28b72e4198573c4a Mon Sep 17 00:00:00 2001 From: mateo-berri <277851410+mateo-berri@users.noreply.github.com> Date: Thu, 17 Sep 2026 17:25:59 -0700 Subject: [PATCH 2/2] fix(bedrock_mantle): resolve gpt-5 sampling rules from the OpenAI catalogue entry --- .../responses/transformation.py | 4 ++ .../llms/openai/responses/transformation.py | 11 +++-- ...bedrock_mantle_responses_transformation.py | 47 ++++++++++++++----- 3 files changed, 47 insertions(+), 15 deletions(-) diff --git a/litellm/llms/bedrock_mantle/responses/transformation.py b/litellm/llms/bedrock_mantle/responses/transformation.py index 57590601a3c..86e20e31d7f 100644 --- a/litellm/llms/bedrock_mantle/responses/transformation.py +++ b/litellm/llms/bedrock_mantle/responses/transformation.py @@ -344,6 +344,10 @@ class BedrockMantleResponsesAPIConfig(BedrockMantleAuthMixin, OpenAIResponsesAPI kept: Final = [item for item, _ in normalized if item is not None] # mutable-ok: ResponseInputParam is a list return kept # pyright: ignore[reportReturnType] # Codex passthrough items sit outside the OpenAI input union + @staticmethod + def _model_map_lookup_name(model: str) -> str: + return model.split("/")[-1].removeprefix("openai.") + def map_openai_params( self, response_api_optional_params: ResponsesAPIOptionalRequestParams, diff --git a/litellm/llms/openai/responses/transformation.py b/litellm/llms/openai/responses/transformation.py index 0d8d6934795..6c1d8698652 100644 --- a/litellm/llms/openai/responses/transformation.py +++ b/litellm/llms/openai/responses/transformation.py @@ -125,6 +125,10 @@ class OpenAIResponsesAPIConfig(BaseResponsesAPIConfig): return False return is_gpt_reasoning_series_name(model) + @staticmethod + def _model_map_lookup_name(model: str) -> str: + return model + @staticmethod def _supports_reasoning_effort_none(model: str) -> bool: """Return True if the model supports reasoning.effort='none'.""" @@ -235,11 +239,12 @@ class OpenAIResponsesAPIConfig(BaseResponsesAPIConfig): status_code=400, ) - if self._is_gpt_5_model(model=model): + lookup_name: Final = self._model_map_lookup_name(model) + if self._is_gpt_5_model(model=lookup_name): reasoning: Final = params.get("reasoning") or {} effort: Final = reasoning.get("effort") if isinstance(reasoning, dict) else None - supports_none: Final = self._supports_reasoning_effort_none(model=model) - effort_is_none: Final = supports_none and self._effort_resolves_to_none(model, effort) + supports_none: Final = self._supports_reasoning_effort_none(model=lookup_name) + effort_is_none: Final = supports_none and self._effort_resolves_to_none(lookup_name, effort) temperature: Final = params.get("temperature") if temperature is not None and temperature != 1: diff --git a/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py b/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py index afd284d31c8..88d9e103f86 100644 --- a/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py +++ b/tests/test_litellm/llms/bedrock_mantle/test_bedrock_mantle_responses_transformation.py @@ -370,26 +370,49 @@ class TestBedrockMantleResponsesTools: class TestBedrockMantleSamplingParams: - """Mantle rejects top_p on its gpt-5 reasoning models and non-default temperature - while reasoning is active, the same rule the OpenAI Responses surface applies, so - drop_params must strip both before the request leaves.""" + """Mantle serves OpenAI's gpt-5 models under their OpenAI sampling rule: top_p and a + non-default temperature are accepted only when reasoning.effort resolves to none, so + the `openai.` catalogue name (region-prefixed on GovCloud) must answer from the OpenAI + model's map entry instead of dropping both params on every request.""" @pytest.mark.parametrize( - "model", + "model, effort, survives", [ - "openai.gpt-5.4", - "openai.gpt-5.5", - "openai.gpt-5.6-luna", + ("openai.gpt-5.4", None, True), + ("openai.gpt-5.5", None, False), + ("openai.gpt-5.6-luna", None, False), + ("openai.gpt-5.6-luna", "none", True), + ("openai.gpt-5.6-luna", "low", False), + ("us-gov-west-1/openai.gpt-5.4", None, True), + ("us-gov-west-1/openai.gpt-5.6-luna", None, False), ], ) - def test_map_openai_params_drops_top_p_and_temperature(self, local_cost_map, model): - params = BedrockMantleResponsesAPIConfig().map_openai_params( - response_api_optional_params={"top_p": 0.9, "temperature": 0.2}, + def test_top_p_and_temperature_follow_the_resolved_effort(self, local_cost_map, model, effort, survives): + params = {"top_p": 0.9, "temperature": 0.2} + if effort is not None: + params["reasoning"] = {"effort": effort} + mapped = BedrockMantleResponsesAPIConfig().map_openai_params( + response_api_optional_params=params, model=model, drop_params=True, ) - assert "top_p" not in params - assert "temperature" not in params + assert ("top_p" in mapped) is survives + assert ("temperature" in mapped) is survives + + def test_top_p_without_drop_params_raises_only_while_reasoning_is_active(self, local_cost_map): + with pytest.raises(litellm.UnsupportedParamsError): + BedrockMantleResponsesAPIConfig().map_openai_params( + response_api_optional_params={"top_p": 0.9}, + model="openai.gpt-5.6-luna", + drop_params=False, + ) + + mapped = BedrockMantleResponsesAPIConfig().map_openai_params( + response_api_optional_params={"top_p": 0.9}, + model="openai.gpt-5.4", + drop_params=False, + ) + assert mapped["top_p"] == 0.9 class TestBedrockMantleResponsesWebSearch: