BerriAI/litellm · error · APIError

LiteLLM: provider returned a response with no 'choices'. Raw

Error message

LiteLLM: provider returned a response with no 'choices'. Raw keys: {list(response_object.keys())}

What it means

While converting a provider dict into a streaming ModelResponse, litellm found the response_object had no non-empty 'choices' key and raised APIError(500) with the raw key list included. This surfaces when a provider (or cache/middleware) returns a well-formed JSON dict that is not a chat completion — e.g. an error payload, moderation payload, or empty object. The message intentionally echoes response_object.keys() so you can identify what the payload actually was.

Source

Thrown at litellm/litellm_core_utils/llm_response_utils/convert_dict_to_response.py:185

        ModelResponse: The converted streaming response object.

    Returns:
        None
    """
    if response_object is None:
        raise Exception("Error in response object format")

    model_response_object: Final = ModelResponseStream()

    if model_response_object is None:
        raise Exception("Error in response creating model response object")

    choice_list: Final[list[StreamingChoices]] = []

    if not response_object.get("choices"):
        from litellm.exceptions import APIError

        raise APIError(
            status_code=500,
            message=(
                f"LiteLLM: provider returned a response with no 'choices'. Raw keys: {list(response_object.keys())}"
            ),
            llm_provider="",
            model="",
        )

    for idx, choice in enumerate(response_object["choices"]):
        if (
            choice["message"].get("tool_calls", None) is not None
            and isinstance(choice["message"]["tool_calls"], list)
            and len(choice["message"]["tool_calls"]) > 0
            and isinstance(choice["message"]["tool_calls"][0], dict)
        ):
            pydantic_tool_calls = []
            for index, t in enumerate(choice["message"]["tool_calls"]):
                if "index" not in t:

View on GitHub (pinned to 6c2dcb801b)

Solutions

Inspect the 'Raw keys' in the message to identify what the payload actually is (error body, empty dict, other response type).
If a custom provider/handler produced it, ensure its translation layer emits {'choices': [...]} for chat completions.
Check provider status pages and retry — some providers emit non-choices JSON on transient faults.
If caching is enabled, verify cache keys don't collide across response types and cached values are chat-shaped.

Example fix

// before (mock/edge server)
return JsonResponse({'id': 'x', 'output': 'hi'})

# after
return JsonResponse({'id': 'x', 'choices': [{'index': 0, 'message': {'role': 'assistant', 'content': 'hi'}, 'finish_reason': 'stop'}]})

Defensive patterns

Strategy: try-catch

Validate before calling

def provider_dict_is_chat_completion(d: dict) -> bool:
    return bool(d.get('choices'))

Try / catch

from litellm.exceptions import APIError
try:
    stream = litellm.completion(**params, stream=True)
except APIError as e:
    if "no 'choices'" in str(e):
        logging.error('provider sent non-completion payload: %s', e.message)
    raise

Prevention

Point mocks and gateways at the OpenAI chat-completion schema (choices required).
Log raw provider payloads at debug level in custom handlers to catch shape drift early.
Monitor for this error per provider — it often flags provider incidents.

When it happens

Trigger: A provider returns {'error': {...}} with HTTP 200; a cached embedding response is replayed into a chat stream path; middleware rewrites the response body and drops 'choices'; Azure/OpenAI-compatible gateways return empty {} on partial failures.

Common situations: Custom API gateways or mock servers that don't include 'choices'; provider outages returning JSON error bodies without error status codes; response-translation bugs in custom handlers; cache collisions between different response types under the same key.

Related errors

AI-assisted analysis of BerriAI/litellm@6c2dcb801b (2026-08-15). Data as JSON: /api/errors/3378d1922020acdb. Report an issue: GitHub.