From 52bf372319b959c49be126472268cc0b7bf1bb8a Mon Sep 17 00:00:00 2001 From: Sameer Kankute Date: Wed, 18 Mar 2026 09:17:57 +0530 Subject: [PATCH] fix(gpt5): treat missing supports_minimal_reasoning_effort as supported Add _is_reasoning_effort_level_explicitly_disabled to use opt-out semantics for minimal effort: unknown/unlisted models pass through, only blocked when the model map explicitly sets supports_minimal_reasoning_effort=false. xhigh keeps opt-in semantics (must be explicitly supported). Adds test for unknown-model passthrough and explicit-disabled detection. Made-with: Cursor --- .../llms/openai/chat/gpt_5_transformation.py | 42 +++++++++++++++++-- .../llms/openai/test_gpt5_transformation.py | 35 ++++++++++++++++ 2 files changed, 73 insertions(+), 4 deletions(-) diff --git a/litellm/llms/openai/chat/gpt_5_transformation.py b/litellm/llms/openai/chat/gpt_5_transformation.py index 8522a97a387..6291f4232d5 100644 --- a/litellm/llms/openai/chat/gpt_5_transformation.py +++ b/litellm/llms/openai/chat/gpt_5_transformation.py @@ -3,7 +3,7 @@ from typing import Optional, Union import litellm -from litellm.utils import _supports_factory +from litellm.utils import _get_model_cost_key, _get_model_info_helper, _supports_factory from .gpt_transformation import OpenAIGPTConfig @@ -113,6 +113,28 @@ class OpenAIGPT5Config(OpenAIGPTConfig): key=f"supports_{level}_reasoning_effort", ) + @classmethod + def _is_reasoning_effort_level_explicitly_disabled( + cls, model: str, level: str + ) -> bool: + """Return True only when the model map explicitly sets the capability to False. + + Unlike ``_supports_reasoning_effort_level`` (which requires an explicit True), + this method returns True only when ``supports_{level}_reasoning_effort`` is + explicitly set to ``False`` in the model map. A missing key is treated as + supported (i.e. this method returns False = not disabled). + + Use this for opt-out checks where unknown models should be allowed through. + """ + try: + key = f"supports_{level}_reasoning_effort" + cost_key = _get_model_cost_key(model) + entry = litellm.model_cost.get(cost_key or model) or {} + val = entry.get(key) + return val is False + except Exception: + return False + def get_supported_openai_params(self, model: str) -> list: if self.is_model_gpt_5_search_model(model): return [ @@ -200,9 +222,8 @@ class OpenAIGPT5Config(OpenAIGPTConfig): if "reasoning_effort" in optional_params: optional_params["reasoning_effort"] = normalized - if effective_effort is not None and ( - effective_effort == "xhigh" or effective_effort == "minimal" - ): + if effective_effort == "xhigh": + # xhigh is an opt-in capability: only allow if model explicitly supports it. if not self._supports_reasoning_effort_level(model, effective_effort): if litellm.drop_params or drop_params: non_default_params.pop("reasoning_effort", None) @@ -213,6 +234,19 @@ class OpenAIGPT5Config(OpenAIGPTConfig): ), status_code=400, ) + elif effective_effort == "minimal": + # minimal is opt-out: unknown models pass through; only block when + # the model map explicitly sets supports_minimal_reasoning_effort=false. + if self._is_reasoning_effort_level_explicitly_disabled(model, effective_effort): + if litellm.drop_params or drop_params: + non_default_params.pop("reasoning_effort", None) + else: + raise litellm.utils.UnsupportedParamsError( + message=( + f"reasoning_effort={effective_effort} is not supported for this model." + ), + status_code=400, + ) ################################################################ # max_tokens is not supported for gpt-5 models on OpenAI API diff --git a/tests/test_litellm/llms/openai/test_gpt5_transformation.py b/tests/test_litellm/llms/openai/test_gpt5_transformation.py index 8ae9bf48a62..535fba16140 100644 --- a/tests/test_litellm/llms/openai/test_gpt5_transformation.py +++ b/tests/test_litellm/llms/openai/test_gpt5_transformation.py @@ -409,6 +409,41 @@ def test_gpt5_supports_reasoning_effort_level_minimal(gpt5_config: OpenAIGPT5Con assert not gpt5_config._supports_reasoning_effort_level("gpt-5.4-nano", "minimal") +def test_gpt5_minimal_explicitly_disabled_check(gpt5_config: OpenAIGPT5Config): + """_is_reasoning_effort_level_explicitly_disabled returns True only for explicit False entries. + + Models with supports_minimal_reasoning_effort=false → disabled. + Models with supports_minimal_reasoning_effort=true (or missing) → not disabled. + """ + assert gpt5_config._is_reasoning_effort_level_explicitly_disabled( + "gpt-5.4-mini", "minimal" + ) + assert gpt5_config._is_reasoning_effort_level_explicitly_disabled( + "gpt-5.4-nano", "minimal" + ) + assert not gpt5_config._is_reasoning_effort_level_explicitly_disabled( + "gpt-5.4", "minimal" + ) + assert not gpt5_config._is_reasoning_effort_level_explicitly_disabled( + "gpt-5.4-pro", "minimal" + ) + + +def test_gpt5_unknown_model_passes_through_minimal(config: OpenAIConfig): + """Unknown/unlisted gpt-5 models should pass reasoning_effort='minimal' through. + + Missing supports_minimal_reasoning_effort key is treated as supported, + not as unsupported, to avoid breaking custom or newly-announced models. + """ + params = config.map_openai_params( + non_default_params={"reasoning_effort": "minimal"}, + optional_params={}, + model="gpt-5.4-turbo-preview", + drop_params=False, + ) + assert params["reasoning_effort"] == "minimal" + + def test_gpt5_normalizes_reasoning_effort_dict_with_summary(config: OpenAIConfig): """Dict with summary/generate_summary is normalized for chat completions.""" params = config.map_openai_params(