Chat Completions: fails with function name for tool_choice parameter w/ streaming enabled #980
Description
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- Have you read the docs? Yes
- Have you searched for related issues? Yes
Describe the bug
A clear and concise description of what the bug is.
This only happens when running with Runner.run_streamed
When a function name is provided to ModelSettings's tool_choice, the converter here will convert it to a dict structure:
@classmethod def convert_tool_choice( cls, tool_choice: Literal["auto", "required", "none"] | str | None ) -> ChatCompletionToolChoiceOptionParam | NotGiven: if tool_choice is None: return NOT_GIVEN elif tool_choice == "auto": return "auto" elif tool_choice == "required": return "required" elif tool_choice == "none": return "none" else: return { "type": "function", "function": { "name": tool_choice, }, } However, at the below line, we restrict the input to be one of the three Literals.
Resulting in the below pydantic validation error:
validated_self = self.__pydantic_validator__.validate_python(data, self_instance=self) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pydantic_core._pydantic_core.ValidationError: 5 validation errors for Response tool_choice.literal['none','auto','required'] Input should be 'none', 'auto' or 'required' [type=literal_error, input_value={'type': 'function', 'fun...ognize_named_entities'}}, input_type=dict] For further information visit https://errors.pydantic.dev/2.11/v/literal_error tool_choice.ToolChoiceTypes.type Input should be 'file_search', 'web_search_preview', 'computer_use_preview', 'web_search_preview_2025_03_11', 'image_generation' or 'code_interpreter' [type=literal_error, input_value='function', input_type=str] For further information visit https://errors.pydantic.dev/2.11/v/literal_error tool_choice.ToolChoiceFunction.name Field required [type=missing, input_value={'type': 'function', 'fun...ognize_named_entities'}}, input_type=dict] For further information visit https://errors.pydantic.dev/2.11/v/missing tool_choice.ToolChoiceMcp.server_label Field required [type=missing, input_value={'type': 'function', 'fun...ognize_named_entities'}}, input_type=dict] For further information visit https://errors.pydantic.dev/2.11/v/missing tool_choice.ToolChoiceMcp.type Input should be 'mcp' [type=literal_error, input_value='function', input_type=str] For further information visit https://errors.pydantic.dev/2.11/v/literal_error Debug information
- Agents SDK version:
v0.1.0 - Python version: Python 3.12
Repro steps
Run with Runner.run_streamed and set the model settings to a tool function name instead of the default three Literals.
Expected behavior
Without any validation issues.