In model.py, the error-handling path inside the __call__ loop has a type mismatch bug: when "error" in responses, return responses["error"] returns a flat List[str] (e.g., ["<json error>", "<json error>"]), but the declared return type is Iterable[Iterable[str]]. Callers expecting a nested structure will silently iterate over individual characters of the error string rather than getting a proper response list. This should be return [responses["error"]] or appended to all_api_responses before returning, consistent with the non-error path.

Additionally, _verify_auth in model.py verifies credentials by making a live API call with self([["test"]]), which consumes billable tokens on every cold start or config validation. The other providers in this repo (e.g., OpenAI's implementation) typically use a lightweight /v1/models endpoint for this. Since MiniMax reportedly lacks that endpoint, it may be worth at minimum documenting this side-effect in a comment, or skipping the verification entirely and relying on the first real call to surface auth errors.

Finally, the _request closure is redefined on every iteration of the outer for prompts_for_doc in prompts loop — moving it outside the loop (accepting prompts_for_doc as a parameter) would be cleaner and avoids the closure capturing a loop variable.