The first iteration of the Ollama response_format passthrough crashed
with 'ChatCompletionRequest object has no attribute response_format'
because the Pydantic request model didn't declare the field at all —
incoming response_format from OpenAI-compatible clients was being
silently dropped at the parsing layer before the provider could see it.
Fix: declare a typed ResponseFormat sub-model with the two OpenAI shapes
('json_object' and 'json_schema'), add it as an optional field on
ChatCompletionRequest, and let the Ollama provider read it directly
without defensive getattr fallbacks.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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