callback_managers = [
                AsyncCallbackManager.configure(
                    cast(Callbacks, callbacks),
                    self.callbacks,
                    self.verbose,
                    cast(List[str], tags),
                    self.tags,
                    cast(Dict[str, Any], metadata),
                    self.metadata,
                )
            ] * len(prompts)
        params = self.dict()
        params["stop"] = stop
        options = {"stop": stop}
        (
            existing_prompts,
            llm_string,
            missing_prompt_idxs,
            missing_prompts,
        ) = get_prompts(params, prompts)
        disregard_cache = self.cache is not None and not self.cache
        new_arg_supported = inspect.signature(self._agenerate).parameters.get(
            "run_manager"
        )
        if langchain.llm_cache is None or disregard_cache:
            if self.cache is not None and self.cache:
                raise ValueError(
                    "Asked to cache, but no cache found at `langchain.cache`."
                )
            run_managers = await asyncio.gather(
                *[
                    callback_manager.on_llm_start(
                        dumpd(self), [prompt], invocation_params=params, options=options
                    )
                    for callback_manager, prompt in zip(callback_managers, prompts)
                ]
            )
            run_managers = [r[0] for r in run_managers]
            output = await self._agenerate_helper(
                prompts, stop, run_managers, bool(new_arg_supported), **kwargs
            )
            return output
        if len(missing_prompts) > 0:
            run_managers = await asyncio.gather(
                *[
                    callback_managers[idx].on_llm_start(
                        dumpd(self),
                        [prompts[idx]],
                        invocation_params=params,