langchain/callbacks/base.py/AsyncCallbackHandler/on_llm_error
class AsyncCallbackHandler:    async def on_llm_error(
        self,
        error: Union[Exception, KeyboardInterrupt],
        *,
        run_id: UUID,
        parent_run_id: Optional[UUID] = None,
        **kwargs: Any,
    ) -> None:
        """Run when LLM errors."""