why make the n= fixed in vllm worker generate_stream method

could you explain the purpose make the n=1 fixed

I want to call the vllm worker directly, but I can not get multipe choice. I checked the code, find this

in generate_stream method

    sampling_params = SamplingParams(
        n=1,
        temperature=temperature,
        top_p=top_p,
        use_beam_search=use_beam_search,
        stop=list(stop),
        stop_token_ids=stop_token_ids,
        max_tokens=max_new_tokens,
        top_k=top_k,
        presence_penalty=presence_penalty,
        frequency_penalty=frequency_penalty,
        best_of=best_of,
    )

Start with the vllm worker's generate_stream method and the SamplingParams construction shown in the issue. Read the surrounding worker implementation and the referenced SamplingParams behavior to determine the intended role of n=1 and whether direct callers can request multiple choices. Done means documenting the rationale and supported behavior.