BerriAI/litellm · error · CometAPIException

KeyError: {e}, Got unexpected response from CometAPI: {chunk

Error message

KeyError: {e}, Got unexpected response from CometAPI: {chunk}

What it means

Error "KeyError: {e}, Got unexpected response from CometAPI: {chunk}" thrown in BerriAI/litellm.

Source

Thrown at litellm/llms/cometapi/chat/transformation.py:189

            # Process choices
            new_choices: Final = []
            for choice in chunk["choices"]:
                # Handle reasoning content if present
                if "delta" in choice and "reasoning" in choice["delta"]:
                    choice["delta"]["reasoning_content"] = choice["delta"].get("reasoning")
                new_choices.append(choice)

            return ModelResponseStream(
                id=chunk["id"],
                object="chat.completion.chunk",
                created=chunk["created"],
                usage=chunk.get("usage"),
                model=chunk["model"],
                choices=new_choices,
            )
        except KeyError as e:
            raise CometAPIException(
                message=f"KeyError: {e}, Got unexpected response from CometAPI: {chunk}",
                status_code=400,
                headers={"Content-Type": "application/json"},
            )
        except Exception as e:
            raise e

View on GitHub (pinned to 6c2dcb801b)

Solutions

1. The CometAPI response chunk had an unexpected shape; check the provider response.

When it happens

Trigger: Thrown at litellm/llms/cometapi/chat/transformation.py:189 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of BerriAI/litellm@6c2dcb801b (2026-08-15). Data as JSON: /api/errors/9fa4f0f3f542ede3. Report an issue: GitHub.