medium severityFireworks AI chat completions API (OpenAI compatible)
API request fails with: "2 request validation errors: Input should be 'auto', 'none', 'any' or 'required', field: 'tool_choice.literal[...]', value: None; Input should be a valid dictionary... field: 'tool_choice.FunctionSelection', value: None" when using Fireworks as OpenAI-compatible endpoint for tool/function calling.
Root cause
Client libraries serialize tool_choice as null/None or use camelCase, but Fireworks API (OpenAI-compatible) expects lowercase string literals ("auto", "none", "any", "required") and rejects invalid values during request validation.[Zed GitHub issue #35434](https://github.com/zed-industries/zed/issues/35434)
fireworks-aitool_choiceschema validationopenai-compatibleserializationnull value