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vllm.entrypoints.openai.serving_responses

logger module-attribute

logger = init_logger(__name__)

OpenAIServingResponses

Bases: OpenAIServing

Source code in vllm/entrypoints/openai/serving_responses.py
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class OpenAIServingResponses(OpenAIServing):

    def __init__(
        self,
        engine_client: EngineClient,
        model_config: ModelConfig,
        models: OpenAIServingModels,
        *,
        request_logger: Optional[RequestLogger],
        chat_template: Optional[str],
        chat_template_content_format: ChatTemplateContentFormatOption,
        return_tokens_as_token_ids: bool = False,
        reasoning_parser: str = "",
        enable_auto_tools: bool = False,
        tool_parser: Optional[str] = None,
        tool_server: Optional[ToolServer] = None,
        enable_prompt_tokens_details: bool = False,
        enable_force_include_usage: bool = False,
        enable_log_outputs: bool = False,
    ) -> None:
        super().__init__(
            engine_client=engine_client,
            model_config=model_config,
            models=models,
            request_logger=request_logger,
            return_tokens_as_token_ids=return_tokens_as_token_ids,
            enable_force_include_usage=enable_force_include_usage,
        )

        self.chat_template = chat_template
        self.chat_template_content_format: Final = chat_template_content_format
        self.enable_log_outputs = enable_log_outputs

        self.reasoning_parser: Optional[Callable[[AnyTokenizer],
                                                 ReasoningParser]] = None
        if reasoning_parser:
            try:
                self.reasoning_parser = (
                    ReasoningParserManager.get_reasoning_parser(
                        reasoning_parser))
                assert self.reasoning_parser is not None
            except Exception as e:
                raise TypeError(
                    f"{reasoning_parser=} has not been registered") from e

        self.enable_prompt_tokens_details = enable_prompt_tokens_details
        self.enable_force_include_usage = enable_force_include_usage
        self.default_sampling_params = (
            self.model_config.get_diff_sampling_param())
        if self.default_sampling_params:
            source = self.model_config.generation_config
            source = "model" if source == "auto" else source
            logger.info("Using default chat sampling params from %s: %s",
                        source, self.default_sampling_params)

        # If False (default), the "store" option is (silently) ignored and the
        # response is not stored. If True, the response is stored in memory.
        # NOTE(woosuk): This may not be intuitive for users, as the default
        # behavior in OpenAI's Responses API is to store the response, but
        # vLLM's default behavior is not.
        self.enable_store = envs.VLLM_ENABLE_RESPONSES_API_STORE
        if self.enable_store:
            logger.warning_once(
                "`VLLM_ENABLE_RESPONSES_API_STORE` is enabled. This may "
                "cause a memory leak since we never remove responses from "
                "the store.")

        self.use_harmony = model_config.hf_config.model_type == "gpt_oss"
        if self.use_harmony:
            logger.warning("For gpt-oss, we ignore --enable-auto-tool-choice "
                           "and always enable tool use.")
            # OpenAI models have two EOS-like tokens: <|return|> and <|call|>.
            # We need to add them to the stop token ids.
            if "stop_token_ids" not in self.default_sampling_params:
                self.default_sampling_params["stop_token_ids"] = []
            self.default_sampling_params["stop_token_ids"].extend(
                get_stop_tokens_for_assistant_actions())

        # set up tool use
        self.enable_auto_tools: bool = enable_auto_tools
        if self.enable_auto_tools:
            logger.info(
                "\"auto\" tool choice has been enabled please note that while"
                " the parallel_tool_calls client option is preset for "
                "compatibility reasons, it will be ignored.")

        # HACK(woosuk): This is a hack. We should use a better store.
        # FIXME: If enable_store=True, this may cause a memory leak since we
        # never remove responses from the store.
        self.response_store: dict[str, ResponsesResponse] = {}
        self.response_store_lock = asyncio.Lock()

        # HACK(woosuk): This is a hack. We should use a better store.
        # FIXME: If enable_store=True, this may cause a memory leak since we
        # never remove messages from the store.
        self.msg_store: dict[str, list[ChatCompletionMessageParam]] = {}

        self.background_tasks: dict[str, asyncio.Task] = {}

        self.tool_server = tool_server

    async def create_responses(
        self,
        request: ResponsesRequest,
        raw_request: Optional[Request] = None,
    ) -> Union[AsyncGenerator[str, None], ResponsesResponse, ErrorResponse]:
        error_check_ret = await self._check_model(request)
        if error_check_ret is not None:
            logger.error("Error with model %s", error_check_ret)
            return error_check_ret

        # If the engine is dead, raise the engine's DEAD_ERROR.
        # This is required for the streaming case, where we return a
        # success status before we actually start generating text :).
        if self.engine_client.errored:
            raise self.engine_client.dead_error

        if request.store and not self.enable_store:
            if request.background:
                return self.create_error_response(
                    err_type="invalid_request_error",
                    message=(
                        "This vLLM engine does not support `store=True` and "
                        "therefore does not support the background mode. To "
                        "enable these features, set the environment variable "
                        "`VLLM_ENABLE_RESPONSES_API_STORE=1` when launching "
                        "the vLLM server."),
                    status_code=HTTPStatus.BAD_REQUEST,
                )
            # Disable the store option.
            # NOTE(woosuk): Although returning an error is possible, we opted
            # to implicitly disable store and process the request anyway, as
            # we assume most users do not intend to actually store the response
            # (i.e., their request's `store=True` just because it's the default
            # value).
            request.store = False
        if self.use_harmony and request.is_include_output_logprobs():
            return self.create_error_response(
                err_type="invalid_request_error",
                message="logprobs are not supported with gpt-oss models",
                status_code=HTTPStatus.BAD_REQUEST,
            )

        # Handle the previous response ID.
        prev_response_id = request.previous_response_id
        if prev_response_id is not None:
            if not prev_response_id.startswith("resp_"):
                return self._make_invalid_id_error(prev_response_id)
            async with self.response_store_lock:
                prev_response = self.response_store.get(prev_response_id)
            if prev_response is None:
                return self._make_not_found_error(prev_response_id)
        else:
            prev_response = None

        try:
            lora_request = self._maybe_get_adapters(request)
            model_name = self._get_model_name(request.model, lora_request)
            tokenizer = await self.engine_client.get_tokenizer(lora_request)

            if self.use_harmony:
                messages, request_prompts, engine_prompts = (
                    self._make_request_with_harmony(request, prev_response))
            else:
                messages, request_prompts, engine_prompts = (
                    await self._make_request(request, prev_response,
                                             tokenizer))

        except (ValueError, TypeError, RuntimeError, jinja2.TemplateError,
                NotImplementedError) as e:
            logger.exception("Error in preprocessing prompt inputs")
            return self.create_error_response(f"{e} {e.__cause__}")

        request_metadata = RequestResponseMetadata(
            request_id=request.request_id)
        if raw_request:
            raw_request.state.request_metadata = request_metadata

        if self.tool_server is not None and isinstance(
                self.tool_server, MCPToolServer
        ) and (request.background or request.stream) and request.tools and any(
                tool.type in ["web_search_preview", "code_interpreter"]
                for tool in request.tools):
            return self.create_error_response(
                "MCP tool server is not supported in background mode and "
                "streaming mode")

        # Schedule the request and get the result generator.
        generators: list[AsyncGenerator[ConversationContext, None]] = []

        builtin_tool_list: list[str] = []
        if self.use_harmony and self.tool_server is not None:
            if self.tool_server.has_tool("browser"):
                builtin_tool_list.append("browser")
            if self.tool_server.has_tool("python"):
                builtin_tool_list.append("python")
        async with AsyncExitStack() as exit_stack:
            try:
                if self.tool_server is not None:
                    # TODO: initialize tool sessions lazily when the session
                    # is actually used.
                    tool_session_ctxs: dict[str, Any] = {
                        tool_name:
                        exit_stack.enter_async_context(
                            self.tool_server.new_session(tool_name))
                        for tool_name in builtin_tool_list
                    }
                    tool_sessions = {}
                    for tool_name in builtin_tool_list:
                        tool_sessions[tool_name] = (
                            await tool_session_ctxs[tool_name])
                else:
                    assert len(builtin_tool_list) == 0
                    tool_sessions = {}
                for i, engine_prompt in enumerate(engine_prompts):
                    default_max_tokens = self.max_model_len - len(
                        engine_prompt["prompt_token_ids"])
                    sampling_params = request.to_sampling_params(
                        default_max_tokens, self.default_sampling_params)

                    trace_headers = (None if raw_request is None else await
                                     self._get_trace_headers(
                                         raw_request.headers))

                    context: ConversationContext
                    if self.use_harmony:
                        if request.stream:
                            context = StreamingHarmonyContext(
                                messages, tool_sessions)
                        else:
                            context = HarmonyContext(messages, tool_sessions)
                    else:
                        context = SimpleContext()
                    generator = self._generate_with_builtin_tools(
                        request_id=request.request_id,
                        request_prompt=request_prompts[i],
                        engine_prompt=engine_prompt,
                        sampling_params=sampling_params,
                        context=context,
                        lora_request=lora_request,
                        priority=request.priority,
                        trace_headers=trace_headers,
                    )
                    generators.append(generator)
            except ValueError as e:
                # TODO: Use a vllm-specific Validation Error
                return self.create_error_response(str(e))

            assert len(generators) == 1
            result_generator, = generators

            # Store the input messages.
            if request.store:
                self.msg_store[request.request_id] = messages

            if request.background:
                created_time = int(time.time())
                response = ResponsesResponse.from_request(
                    request,
                    sampling_params,
                    model_name=model_name,
                    created_time=created_time,
                    output=[],
                    status="queued",
                    usage=None,
                )
                async with self.response_store_lock:
                    self.response_store[response.id] = response

                # Run the request in the background.
                task = asyncio.create_task(
                    self._run_background_request(
                        request,
                        sampling_params,
                        result_generator,
                        context,
                        model_name,
                        tokenizer,
                        request_metadata,
                        created_time,
                    ),
                    name=f"create_{response.id}",
                )

                # For cleanup.
                response_id = response.id
                self.background_tasks[response_id] = task
                task.add_done_callback(
                    lambda _: self.background_tasks.pop(response_id, None))
                return response

            if request.stream:
                return self.responses_stream_generator(
                    request,
                    sampling_params,
                    result_generator,
                    context,
                    model_name,
                    tokenizer,
                    request_metadata,
                )

            try:
                return await self.responses_full_generator(
                    request,
                    sampling_params,
                    result_generator,
                    context,
                    model_name,
                    tokenizer,
                    request_metadata,
                )
            except Exception as e:
                return self.create_error_response(str(e))
        return self.create_error_response("Should not reach here")

    async def _make_request(
        self,
        request: ResponsesRequest,
        prev_response: Optional[ResponsesResponse],
        tokenizer: AnyTokenizer,
    ):
        if len(request.tools) > 0:
            raise NotImplementedError(
                "Tool use is not supported in Responses API without Harmony")
        # Construct the input messages.
        messages = self._construct_input_messages(request, prev_response)
        _, request_prompts, engine_prompts = await self._preprocess_chat(
            request,
            tokenizer,
            messages,
            chat_template=self.chat_template,
            chat_template_content_format=self.chat_template_content_format,
        )
        return messages, request_prompts, engine_prompts

    def _make_request_with_harmony(
        self,
        request: ResponsesRequest,
        prev_response: Optional[ResponsesResponse],
    ):
        if request.tool_choice != "auto":
            raise NotImplementedError(
                "Only 'auto' tool_choice is supported in "
                "response API with Harmony")
        messages = self._construct_input_messages_with_harmony(
            request, prev_response)
        prompt_token_ids = render_for_completion(messages)
        engine_prompt = EngineTokensPrompt(prompt_token_ids=prompt_token_ids)

        # Add cache_salt if provided in the request
        if request.cache_salt is not None:
            engine_prompt["cache_salt"] = request.cache_salt

        return messages, [prompt_token_ids], [engine_prompt]

    async def responses_full_generator(
        self,
        request: ResponsesRequest,
        sampling_params: SamplingParams,
        result_generator: AsyncIterator[ConversationContext],
        context: ConversationContext,
        model_name: str,
        tokenizer: AnyTokenizer,
        request_metadata: RequestResponseMetadata,
        created_time: Optional[int] = None,
    ) -> Union[ErrorResponse, ResponsesResponse]:
        if created_time is None:
            created_time = int(time.time())

        try:
            async for _ in result_generator:
                pass
        except asyncio.CancelledError:
            return self.create_error_response("Client disconnected")
        except ValueError as e:
            # TODO: Use a vllm-specific Validation Error
            return self.create_error_response(str(e))

        if self.use_harmony:
            assert isinstance(context, HarmonyContext)
            output = self._make_response_output_items_with_harmony(context)
            # TODO: these are all 0 for now!
            num_prompt_tokens = context.num_prompt_tokens
            num_generated_tokens = context.num_output_tokens
            num_cached_tokens = context.num_cached_tokens
            num_reasoning_tokens = context.num_reasoning_tokens
        else:
            assert isinstance(context, SimpleContext)
            final_res = context.last_output
            assert final_res is not None
            assert len(final_res.outputs) == 1
            final_output = final_res.outputs[0]

            output = self._make_response_output_items(request, final_output,
                                                      tokenizer)

            # Calculate usage.
            assert final_res.prompt_token_ids is not None
            num_prompt_tokens = len(final_res.prompt_token_ids)
            num_generated_tokens = len(final_output.token_ids)
            num_cached_tokens = final_res.num_cached_tokens
            num_reasoning_tokens = 0

        usage = ResponseUsage(
            input_tokens=num_prompt_tokens,
            output_tokens=num_generated_tokens,
            total_tokens=num_prompt_tokens + num_generated_tokens,
            input_tokens_details=InputTokensDetails(
                cached_tokens=num_cached_tokens),
            output_tokens_details=OutputTokensDetails(
                reasoning_tokens=num_reasoning_tokens),
        )
        response = ResponsesResponse.from_request(
            request,
            sampling_params,
            model_name=model_name,
            created_time=created_time,
            output=output,
            status="completed",
            usage=usage,
        )

        if request.store:
            async with self.response_store_lock:
                stored_response = self.response_store.get(response.id)
                # If the response is already cancelled, don't update it.
                if (stored_response is None
                        or stored_response.status != "cancelled"):
                    self.response_store[response.id] = response
        return response

    def _topk_logprobs(self, logprobs: dict[int,
                                            SampleLogprob], top_logprobs: int,
                       tokenizer: AnyTokenizer) -> list[LogprobTopLogprob]:
        """Returns the top-k logprobs from the logprobs dictionary."""
        out = []
        for i, (token_id, _logprob) in enumerate(logprobs.items()):
            if i >= top_logprobs:
                break
            text = _logprob.decoded_token if _logprob.decoded_token \
                is not None else tokenizer.decode([token_id])
            out.append(
                LogprobTopLogprob(
                    token=text,
                    logprob=max(_logprob.logprob, -9999.0),
                    bytes=list(text.encode("utf-8", errors="replace")),
                ))
        return out

    def _create_response_logprobs(
            self,
            token_ids: Sequence[int],
            logprobs: Optional[SampleLogprobs],
            tokenizer: AnyTokenizer,
            top_logprobs: Optional[int] = None) -> list[Logprob]:
        assert logprobs is not None, "logprobs must be provided"
        assert len(token_ids) == len(logprobs), (
            "token_ids and logprobs.token_ids must have the same length")
        out = []
        for i, token_id in enumerate(token_ids):
            logprob = logprobs[i]
            token_logprob = logprob[token_id]
            text = token_logprob.decoded_token if token_logprob.decoded_token \
                is not None else tokenizer.decode([token_id])
            out.append(
                Logprob(
                    token=text,
                    logprob=max(token_logprob.logprob, -9999.0),
                    bytes=list(text.encode("utf-8", errors="replace")),
                    top_logprobs=self._topk_logprobs(logprob,
                                                     top_logprobs=top_logprobs,
                                                     tokenizer=tokenizer)
                    if top_logprobs else [],
                ))
        return out

    def _make_response_output_items(
        self,
        request: ResponsesRequest,
        final_output: CompletionOutput,
        tokenizer: AnyTokenizer,
    ) -> list[ResponseOutputItem]:
        if self.reasoning_parser:
            try:
                reasoning_parser = self.reasoning_parser(tokenizer)
            except RuntimeError as e:
                logger.exception("Error in reasoning parser creation.")
                raise e

            reasoning_content, content = (
                reasoning_parser.extract_reasoning_content(final_output.text,
                                                           request=request))
        else:
            reasoning_content = None
            content = final_output.text

        # Log complete response if output logging is enabled
        if self.enable_log_outputs and self.request_logger:
            output_text = ""
            if content:
                output_text = content
            elif reasoning_content:
                output_text = f"[reasoning: {reasoning_content}]"

            if output_text:
                self.request_logger.log_outputs(
                    request_id=request.request_id,
                    outputs=output_text,
                    output_token_ids=final_output.token_ids,
                    finish_reason=final_output.finish_reason,
                    is_streaming=False,
                    delta=False,
                )

        output = []
        if reasoning_content:
            reasoning_item = ResponseReasoningItem(
                id=f"rs_{random_uuid()}",
                summary=[],
                type="reasoning",
                content=[
                    ResponseReasoningTextContent(text=reasoning_content,
                                                 type="reasoning_text")
                ],
                status=None,  # NOTE: Only the last output item has status.
            )
            output.append(reasoning_item)
        if content:
            output_text = ResponseOutputText(
                text=content,
                annotations=[],  # TODO
                type="output_text",
                logprobs=self._create_response_logprobs(
                    token_ids=final_output.token_ids,
                    logprobs=final_output.logprobs,
                    tokenizer=tokenizer,
                    top_logprobs=request.top_logprobs,
                ) if request.is_include_output_logprobs() else None,
            )
            message = ResponseOutputMessage(
                id=f"msg_{random_uuid()}",
                content=[output_text],
                role="assistant",
                status="completed",
                type="message",
            )
            output.append(message)
        return output

    def _make_response_output_items_with_harmony(
        self,
        context: HarmonyContext,
    ) -> list[ResponseOutputItem]:
        output_items = []
        num_init_messages = context.num_init_messages
        for msg in context.messages[num_init_messages:]:
            output_items.extend(parse_output_message(msg))
        # Handle the generation stopped in the middle (if any).
        last_items = parse_remaining_state(context.parser)
        if last_items:
            output_items.extend(last_items)
        return output_items

    def _construct_input_messages(
        self,
        request: ResponsesRequest,
        prev_response: Optional[ResponsesResponse] = None,
    ) -> list[ChatCompletionMessageParam]:
        messages: list[ChatCompletionMessageParam] = []
        if request.instructions:
            messages.append({
                "role": "system",
                "content": request.instructions,
            })

        # Prepend the conversation history.
        if prev_response is not None:
            # Add the previous messages.
            prev_msg = self.msg_store[prev_response.id]
            messages.extend(prev_msg)

            # Add the previous output.
            for output_item in prev_response.output:
                # NOTE: We skip the reasoning output.
                if isinstance(output_item, ResponseOutputMessage):
                    for content in output_item.content:
                        messages.append({
                            "role": "assistant",
                            "content": content.text,
                        })

        # Append the new input.
        # Responses API supports simple text inputs without chat format.
        if isinstance(request.input, str):
            messages.append({"role": "user", "content": request.input})
        else:
            messages.extend(request.input)  # type: ignore
        return messages

    def _construct_input_messages_with_harmony(
        self,
        request: ResponsesRequest,
        prev_response: Optional[ResponsesResponse],
    ) -> list[OpenAIHarmonyMessage]:
        messages: list[OpenAIHarmonyMessage] = []
        if prev_response is None:
            # New conversation.
            reasoning_effort = (request.reasoning.effort
                                if request.reasoning else None)
            tool_types = [tool.type for tool in request.tools]
            enable_browser = ("web_search_preview" in tool_types
                              and self.tool_server is not None
                              and self.tool_server.has_tool("browser"))
            enable_code_interpreter = ("code_interpreter" in tool_types
                                       and self.tool_server is not None
                                       and self.tool_server.has_tool("python"))
            sys_msg = get_system_message(
                reasoning_effort=reasoning_effort,
                browser_description=self.tool_server.get_tool_description(
                    "browser")
                if enable_browser and self.tool_server is not None else None,
                python_description=self.tool_server.get_tool_description(
                    "python") if enable_code_interpreter
                and self.tool_server is not None else None,
            )
            messages.append(sys_msg)
            dev_msg = get_developer_message(request.instructions,
                                            request.tools)
            messages.append(dev_msg)
        else:
            # Continue the previous conversation.
            # FIXME(woosuk): Currently, request params like reasoning and
            # instructions are ignored.
            prev_msgs = self.msg_store[prev_response.id]
            # Remove the previous chain-of-thoughts if there is a new "final"
            # message. Note that this also removes these messages from the
            # msg_store.
            if len(prev_msgs) > 0:
                last_msg = prev_msgs[-1]
                assert isinstance(last_msg, OpenAIHarmonyMessage)
                if last_msg.channel == "final":
                    prev_final_msg_idx = -1
                    for i in range(len(prev_msgs) - 2, -1, -1):
                        prev_msg_i = prev_msgs[i]
                        assert isinstance(prev_msg_i, OpenAIHarmonyMessage)
                        if prev_msg_i.channel == "final":
                            prev_final_msg_idx = i
                            break
                    recent_turn_msgs = prev_msgs[prev_final_msg_idx + 1:]
                    del prev_msgs[prev_final_msg_idx + 1:]
                    for msg in recent_turn_msgs:
                        assert isinstance(msg, OpenAIHarmonyMessage)
                        if msg.channel != "analysis":
                            prev_msgs.append(msg)
            messages.extend(prev_msgs)
        # Append the new input.
        # Reponses API supports simple text inputs without chat format.
        if isinstance(request.input, str):
            messages.append(get_user_message(request.input))
        else:
            if prev_response is not None:
                prev_outputs = copy(prev_response.output)
            else:
                prev_outputs = []
            for response_msg in request.input:
                messages.append(
                    parse_response_input(response_msg, prev_outputs))
                # User passes in a a tool call request and its output. We need
                # to add the tool call request to prev_outputs so that the
                # parse_response_input can find the tool call request when
                # parsing the tool call output.
                if isinstance(response_msg, ResponseFunctionToolCall):
                    prev_outputs.append(response_msg)
        return messages

    async def _run_background_request(
        self,
        request: ResponsesRequest,
        *args,
        **kwargs,
    ):
        try:
            response = await self.responses_full_generator(
                request, *args, **kwargs)
        except Exception as e:
            logger.exception("Background request failed for %s",
                             request.request_id)
            response = self.create_error_response(str(e))

        if isinstance(response, ErrorResponse):
            # If the request has failed, update the status to "failed".
            response_id = request.request_id
            async with self.response_store_lock:
                stored_response = self.response_store.get(response_id)
                assert stored_response is not None
                if stored_response.status not in ("completed", "cancelled"):
                    stored_response.status = "failed"

    async def retrieve_responses(
        self,
        response_id: str,
    ) -> Union[ErrorResponse, ResponsesResponse]:
        if not response_id.startswith("resp_"):
            return self._make_invalid_id_error(response_id)

        async with self.response_store_lock:
            response = self.response_store.get(response_id)

        if response is None:
            return self._make_not_found_error(response_id)
        return response

    async def cancel_responses(
        self,
        response_id: str,
    ) -> Union[ErrorResponse, ResponsesResponse]:
        if not response_id.startswith("resp_"):
            return self._make_invalid_id_error(response_id)

        async with self.response_store_lock:
            response = self.response_store.get(response_id)
            if response is None:
                return self._make_not_found_error(response_id)

            prev_status = response.status
            if prev_status not in ("queued", "in_progress"):
                return self.create_error_response(
                    err_type="invalid_request_error",
                    message="Cannot cancel a synchronous response.",
                )

            # Update the status to "cancelled".
            response.status = "cancelled"

        # Abort the request.
        if (task := self.background_tasks.get(response_id)):
            task.cancel()
            try:
                await task
            except asyncio.CancelledError:
                logger.exception("Background task for %s was cancelled",
                                 response_id)
        return response

    def _make_invalid_id_error(self, response_id: str) -> ErrorResponse:
        return self.create_error_response(
            err_type="invalid_request_error",
            message=(f"Invalid 'response_id': '{response_id}'. "
                     "Expected an ID that begins with 'resp'."),
        )

    def _make_not_found_error(self, response_id: str) -> ErrorResponse:
        return self.create_error_response(
            err_type="invalid_request_error",
            message=f"Response with id '{response_id}' not found.",
            status_code=HTTPStatus.NOT_FOUND,
        )

    def _make_store_not_supported_error(self) -> ErrorResponse:
        return self.create_error_response(
            err_type="invalid_request_error",
            message=("`store=True` (default) is not supported. Please set "
                     "`store=False` in Responses API or set "
                     "`VLLM_ENABLE_RESPONSES_API_STORE=1` in the env var when "
                     "starting the vLLM server."),
            status_code=HTTPStatus.BAD_REQUEST,
        )

    async def responses_stream_generator(
        self,
        request: ResponsesRequest,
        sampling_params: SamplingParams,
        result_generator: AsyncIterator[Optional[ConversationContext]],
        context: ConversationContext,
        model_name: str,
        tokenizer: AnyTokenizer,
        request_metadata: RequestResponseMetadata,
        created_time: Optional[int] = None,
    ) -> AsyncGenerator[str, None]:
        # TODO:
        # 1. Handle disconnect

        if not isinstance(context, StreamingHarmonyContext):
            raise NotImplementedError(
                "Streaming is not supported for responses API without Harmony."
            )

        created_time = created_time or int(time.time())

        sequence_number = 0

        def _send_event(event: BaseModel):
            nonlocal sequence_number
            # Set sequence_number if the event has this attribute
            if hasattr(event, 'sequence_number'):
                event.sequence_number = sequence_number
            sequence_number += 1
            # Get event type from the event's type field if it exists
            event_type = getattr(event, 'type', 'unknown')
            return (f"event: {event_type}\n"
                    f"data: {event.model_dump_json(indent=None)}\n\n")

        current_content_index = 0  # FIXME: this number is never changed
        current_output_index = 0
        current_item_id = ""  # FIXME: this number is never changed
        sent_output_item_added = False

        initial_response = ResponsesResponse.from_request(
            request,
            sampling_params,
            model_name=model_name,
            created_time=created_time,
            output=[],
            status="in_progress",
            usage=None,
        ).model_dump()
        yield _send_event(
            ResponseCreatedEvent(
                type="response.created",
                sequence_number=-1,
                response=initial_response,
            ))
        yield _send_event(
            ResponseInProgressEvent(
                type="response.in_progress",
                sequence_number=-1,
                response=initial_response,
            ))

        async for ctx in result_generator:

            assert isinstance(ctx, StreamingHarmonyContext)

            if ctx.is_expecting_start():
                current_output_index += 1
                sent_output_item_added = False

                if len(ctx.parser.messages) > 0:
                    previous_item = ctx.parser.messages[-1]
                    if previous_item.recipient is not None:
                        # Deal with tool call here
                        pass
                    elif previous_item.channel == "analysis":
                        reasoning_item = ResponseReasoningItem(
                            type="reasoning",
                            content=[
                                ResponseReasoningTextContent(
                                    text=previous_item.content[0].text,
                                    type="reasoning_text",
                                ),
                            ],
                            status="completed",
                            id=current_item_id,
                            summary=[],
                        )
                        yield _send_event(
                            ResponseReasoningTextDoneEvent(
                                type="response.reasoning_text.done",
                                item_id=current_item_id,
                                sequence_number=-1,
                                output_index=current_output_index,
                                content_index=current_content_index,
                                text=previous_item.content[0].text,
                            ))
                        yield _send_event(
                            ResponseOutputItemDoneEvent(
                                type="response.output_item.done",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item=reasoning_item,
                            ))
                    elif previous_item.channel == "final":
                        text_content = ResponseOutputText(
                            type="output_text",
                            text=previous_item.content[0].text,
                            annotations=[],
                        )
                        yield _send_event(
                            openai_responses_types.ResponseTextDoneEvent(
                                type="response.output_text.done",
                                sequence_number=-1,
                                output_index=current_output_index,
                                content_index=current_content_index,
                                text=previous_item.content[0].text,
                                logprobs=[],
                                item_id=current_item_id,
                            ))
                        yield _send_event(
                            openai_responses_types.
                            ResponseContentPartDoneEvent(
                                type="response.content_part.done",
                                sequence_number=-1,
                                item_id=current_item_id,
                                output_index=current_output_index,
                                content_index=current_content_index,
                                part=text_content,
                            ))
                        yield _send_event(
                            openai_responses_types.ResponseOutputItemDoneEvent(
                                type="response.output_item.done",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item=ResponseOutputMessage(
                                    id=current_item_id,
                                    type="message",
                                    role="assistant",
                                    content=[text_content],
                                    status="completed",
                                ),
                            ))

            if ctx.parser.last_content_delta:
                if (ctx.parser.current_channel == "final"
                        and ctx.parser.current_recipient is None):
                    if not sent_output_item_added:
                        sent_output_item_added = True
                        yield _send_event(
                            openai_responses_types.
                            ResponseOutputItemAddedEvent(
                                type="response.output_item.added",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item=openai_responses_types.
                                ResponseOutputMessage(
                                    id=current_item_id,
                                    type="message",
                                    role="assistant",
                                    content=[],
                                    status="in_progress",
                                ),
                            ))
                        yield _send_event(
                            openai_responses_types.
                            ResponseContentPartAddedEvent(
                                type="response.content_part.added",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item_id=current_item_id,
                                content_index=current_content_index,
                                part=openai_responses_types.ResponseOutputText(
                                    type="output_text",
                                    text="",
                                    annotations=[],
                                    logprobs=[],
                                ),
                            ))
                    yield _send_event(
                        openai_responses_types.ResponseTextDeltaEvent(
                            type="response.output_text.delta",
                            sequence_number=-1,
                            content_index=current_content_index,
                            output_index=current_output_index,
                            item_id=current_item_id,
                            delta=ctx.parser.last_content_delta,
                            # TODO, use logprobs from ctx.last_request_output
                            logprobs=[],
                        ))
                elif (ctx.parser.current_channel == "analysis"
                      and ctx.parser.current_recipient is None):
                    if not sent_output_item_added:
                        sent_output_item_added = True
                        yield _send_event(
                            openai_responses_types.
                            ResponseOutputItemAddedEvent(
                                type="response.output_item.added",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item=openai_responses_types.
                                ResponseReasoningItem(
                                    type="reasoning",
                                    id=current_item_id,
                                    summary=[],
                                    status="in_progress",
                                ),
                            ))
                        yield _send_event(
                            openai_responses_types.
                            ResponseContentPartAddedEvent(
                                type="response.content_part.added",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item_id=current_item_id,
                                content_index=current_content_index,
                                part=openai_responses_types.ResponseOutputText(
                                    type="output_text",
                                    text="",
                                    annotations=[],
                                    logprobs=[],
                                ),
                            ))
                    yield _send_event(
                        ResponseReasoningTextDeltaEvent(
                            type="response.reasoning_text.delta",
                            item_id=current_item_id,
                            output_index=current_output_index,
                            content_index=current_content_index,
                            delta=ctx.parser.last_content_delta,
                            sequence_number=-1,
                        ))
                # built-in tools will be triggered on the analysis channel
                # However, occasionally built-in tools will
                # still be output to commentary.
                elif (ctx.parser.current_channel == "commentary"
                      or ctx.parser.current_channel == "analysis"
                      ) and ctx.parser.current_recipient == "python":
                    if not sent_output_item_added:
                        sent_output_item_added = True
                        yield _send_event(
                            openai_responses_types.
                            ResponseOutputItemAddedEvent(
                                type="response.output_item.added",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item=openai_responses_types.
                                ResponseCodeInterpreterToolCallParam(
                                    type="code_interpreter_call",
                                    id=current_item_id,
                                    code=None,
                                    container_id="auto",
                                    outputs=None,
                                    status="in_progress",
                                ),
                            ))
                        yield _send_event(
                            openai_responses_types.
                            ResponseCodeInterpreterCallInProgressEvent(
                                type=
                                "response.code_interpreter_call.in_progress",
                                sequence_number=-1,
                                output_index=current_output_index,
                                item_id=current_item_id,
                            ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseCodeInterpreterCallCodeDeltaEvent(
                            type="response.code_interpreter_call_code.delta",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                            delta=ctx.parser.last_content_delta,
                        ))
            if ctx.is_assistant_action_turn() and len(ctx.parser.messages) > 0:
                previous_item = ctx.parser.messages[-1]
                if (self.tool_server is not None
                        and self.tool_server.has_tool("browser")
                        and previous_item.recipient is not None
                        and previous_item.recipient.startswith("browser.")):
                    function_name = previous_item.recipient[len("browser."):]
                    action = None
                    parsed_args = json.loads(previous_item.content[0].text)
                    if function_name == "search":
                        action = (openai_responses_types.
                                  response_function_web_search.ActionSearch(
                                      type="search",
                                      query=parsed_args["query"],
                                  ))
                    elif function_name == "open":
                        action = (
                            openai_responses_types.
                            response_function_web_search.ActionOpenPage(
                                type="open_page",
                                # TODO: translate to url
                                url=f"cursor:{parsed_args.get('cursor', '')}",
                            ))
                    elif function_name == "find":
                        action = (
                            openai_responses_types.
                            response_function_web_search.ActionFind(
                                type="find",
                                pattern=parsed_args["pattern"],
                                # TODO: translate to url
                                url=f"cursor:{parsed_args.get('cursor', '')}",
                            ))
                    else:
                        raise ValueError(
                            f"Unknown function name: {function_name}")

                    yield _send_event(
                        openai_responses_types.ResponseOutputItemAddedEvent(
                            type="response.output_item.added",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=openai_responses_types.
                            response_function_web_search.
                            ResponseFunctionWebSearch(
                                # TODO: generate a unique id for web search call
                                type="web_search_call",
                                id=current_item_id,
                                action=action,
                                status="in_progress",
                            ),
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseWebSearchCallInProgressEvent(
                            type="response.web_search_call.in_progress",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseWebSearchCallSearchingEvent(
                            type="response.web_search_call.searching",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                        ))

                    # enqueue
                    yield _send_event(
                        openai_responses_types.
                        ResponseWebSearchCallCompletedEvent(
                            type="response.web_search_call.completed",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                        ))
                    yield _send_event(
                        openai_responses_types.ResponseOutputItemDoneEvent(
                            type="response.output_item.done",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=openai_responses_types.
                            ResponseFunctionWebSearch(
                                type="web_search_call",
                                id=current_item_id,
                                action=action,
                                status="completed",
                            ),
                        ))

                if (self.tool_server is not None
                        and self.tool_server.has_tool("python")
                        and previous_item.recipient is not None
                        and previous_item.recipient.startswith("python")):
                    yield _send_event(
                        openai_responses_types.
                        ResponseCodeInterpreterCallCodeDoneEvent(
                            type="response.code_interpreter_call_code.done",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                            code=previous_item.content[0].text,
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseCodeInterpreterCallInterpretingEvent(
                            type="response.code_interpreter_call.interpreting",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseCodeInterpreterCallCompletedEvent(
                            type="response.code_interpreter_call.completed",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                        ))
                    yield _send_event(
                        openai_responses_types.ResponseOutputItemDoneEvent(
                            type="response.output_item.done",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=openai_responses_types.
                            ResponseCodeInterpreterToolCallParam(
                                type="code_interpreter_call",
                                id=current_item_id,
                                code=previous_item.content[0].text,
                                container_id="auto",
                                # TODO: add outputs here
                                outputs=[],
                                status="completed",
                            ),
                        ))

        async def empty_async_generator():
            # A hack to trick Python to think this is a generator but in fact
            # it immediately returns.
            if False:
                yield

        final_response = await self.responses_full_generator(
            request,
            sampling_params,
            empty_async_generator(),
            context,
            model_name,
            tokenizer,
            request_metadata,
            created_time=created_time,
        )
        yield _send_event(
            openai_responses_types.ResponseCompletedEvent(
                type="response.completed",
                sequence_number=-1,
                response=final_response.model_dump(),
            ))

background_tasks instance-attribute

background_tasks: dict[str, Task] = {}

chat_template instance-attribute

chat_template = chat_template

chat_template_content_format instance-attribute

chat_template_content_format: Final = (
    chat_template_content_format
)

default_sampling_params instance-attribute

default_sampling_params = get_diff_sampling_param()

enable_auto_tools instance-attribute

enable_auto_tools: bool = enable_auto_tools

enable_force_include_usage instance-attribute

enable_force_include_usage = enable_force_include_usage

enable_log_outputs instance-attribute

enable_log_outputs = enable_log_outputs

enable_prompt_tokens_details instance-attribute

enable_prompt_tokens_details = enable_prompt_tokens_details

enable_store instance-attribute

msg_store instance-attribute

reasoning_parser instance-attribute

reasoning_parser: Optional[
    Callable[[AnyTokenizer], ReasoningParser]
] = get_reasoning_parser(reasoning_parser)

response_store instance-attribute

response_store: dict[str, ResponsesResponse] = {}

response_store_lock instance-attribute

response_store_lock = Lock()

tool_server instance-attribute

tool_server = tool_server

use_harmony instance-attribute

use_harmony = model_type == 'gpt_oss'

__init__

__init__(
    engine_client: EngineClient,
    model_config: ModelConfig,
    models: OpenAIServingModels,
    *,
    request_logger: Optional[RequestLogger],
    chat_template: Optional[str],
    chat_template_content_format: ChatTemplateContentFormatOption,
    return_tokens_as_token_ids: bool = False,
    reasoning_parser: str = "",
    enable_auto_tools: bool = False,
    tool_parser: Optional[str] = None,
    tool_server: Optional[ToolServer] = None,
    enable_prompt_tokens_details: bool = False,
    enable_force_include_usage: bool = False,
    enable_log_outputs: bool = False,
) -> None
Source code in vllm/entrypoints/openai/serving_responses.py
def __init__(
    self,
    engine_client: EngineClient,
    model_config: ModelConfig,
    models: OpenAIServingModels,
    *,
    request_logger: Optional[RequestLogger],
    chat_template: Optional[str],
    chat_template_content_format: ChatTemplateContentFormatOption,
    return_tokens_as_token_ids: bool = False,
    reasoning_parser: str = "",
    enable_auto_tools: bool = False,
    tool_parser: Optional[str] = None,
    tool_server: Optional[ToolServer] = None,
    enable_prompt_tokens_details: bool = False,
    enable_force_include_usage: bool = False,
    enable_log_outputs: bool = False,
) -> None:
    super().__init__(
        engine_client=engine_client,
        model_config=model_config,
        models=models,
        request_logger=request_logger,
        return_tokens_as_token_ids=return_tokens_as_token_ids,
        enable_force_include_usage=enable_force_include_usage,
    )

    self.chat_template = chat_template
    self.chat_template_content_format: Final = chat_template_content_format
    self.enable_log_outputs = enable_log_outputs

    self.reasoning_parser: Optional[Callable[[AnyTokenizer],
                                             ReasoningParser]] = None
    if reasoning_parser:
        try:
            self.reasoning_parser = (
                ReasoningParserManager.get_reasoning_parser(
                    reasoning_parser))
            assert self.reasoning_parser is not None
        except Exception as e:
            raise TypeError(
                f"{reasoning_parser=} has not been registered") from e

    self.enable_prompt_tokens_details = enable_prompt_tokens_details
    self.enable_force_include_usage = enable_force_include_usage
    self.default_sampling_params = (
        self.model_config.get_diff_sampling_param())
    if self.default_sampling_params:
        source = self.model_config.generation_config
        source = "model" if source == "auto" else source
        logger.info("Using default chat sampling params from %s: %s",
                    source, self.default_sampling_params)

    # If False (default), the "store" option is (silently) ignored and the
    # response is not stored. If True, the response is stored in memory.
    # NOTE(woosuk): This may not be intuitive for users, as the default
    # behavior in OpenAI's Responses API is to store the response, but
    # vLLM's default behavior is not.
    self.enable_store = envs.VLLM_ENABLE_RESPONSES_API_STORE
    if self.enable_store:
        logger.warning_once(
            "`VLLM_ENABLE_RESPONSES_API_STORE` is enabled. This may "
            "cause a memory leak since we never remove responses from "
            "the store.")

    self.use_harmony = model_config.hf_config.model_type == "gpt_oss"
    if self.use_harmony:
        logger.warning("For gpt-oss, we ignore --enable-auto-tool-choice "
                       "and always enable tool use.")
        # OpenAI models have two EOS-like tokens: <|return|> and <|call|>.
        # We need to add them to the stop token ids.
        if "stop_token_ids" not in self.default_sampling_params:
            self.default_sampling_params["stop_token_ids"] = []
        self.default_sampling_params["stop_token_ids"].extend(
            get_stop_tokens_for_assistant_actions())

    # set up tool use
    self.enable_auto_tools: bool = enable_auto_tools
    if self.enable_auto_tools:
        logger.info(
            "\"auto\" tool choice has been enabled please note that while"
            " the parallel_tool_calls client option is preset for "
            "compatibility reasons, it will be ignored.")

    # HACK(woosuk): This is a hack. We should use a better store.
    # FIXME: If enable_store=True, this may cause a memory leak since we
    # never remove responses from the store.
    self.response_store: dict[str, ResponsesResponse] = {}
    self.response_store_lock = asyncio.Lock()

    # HACK(woosuk): This is a hack. We should use a better store.
    # FIXME: If enable_store=True, this may cause a memory leak since we
    # never remove messages from the store.
    self.msg_store: dict[str, list[ChatCompletionMessageParam]] = {}

    self.background_tasks: dict[str, asyncio.Task] = {}

    self.tool_server = tool_server

_construct_input_messages

_construct_input_messages(
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse] = None,
) -> list[ChatCompletionMessageParam]
Source code in vllm/entrypoints/openai/serving_responses.py
def _construct_input_messages(
    self,
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse] = None,
) -> list[ChatCompletionMessageParam]:
    messages: list[ChatCompletionMessageParam] = []
    if request.instructions:
        messages.append({
            "role": "system",
            "content": request.instructions,
        })

    # Prepend the conversation history.
    if prev_response is not None:
        # Add the previous messages.
        prev_msg = self.msg_store[prev_response.id]
        messages.extend(prev_msg)

        # Add the previous output.
        for output_item in prev_response.output:
            # NOTE: We skip the reasoning output.
            if isinstance(output_item, ResponseOutputMessage):
                for content in output_item.content:
                    messages.append({
                        "role": "assistant",
                        "content": content.text,
                    })

    # Append the new input.
    # Responses API supports simple text inputs without chat format.
    if isinstance(request.input, str):
        messages.append({"role": "user", "content": request.input})
    else:
        messages.extend(request.input)  # type: ignore
    return messages

_construct_input_messages_with_harmony

_construct_input_messages_with_harmony(
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse],
) -> list[Message]
Source code in vllm/entrypoints/openai/serving_responses.py
def _construct_input_messages_with_harmony(
    self,
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse],
) -> list[OpenAIHarmonyMessage]:
    messages: list[OpenAIHarmonyMessage] = []
    if prev_response is None:
        # New conversation.
        reasoning_effort = (request.reasoning.effort
                            if request.reasoning else None)
        tool_types = [tool.type for tool in request.tools]
        enable_browser = ("web_search_preview" in tool_types
                          and self.tool_server is not None
                          and self.tool_server.has_tool("browser"))
        enable_code_interpreter = ("code_interpreter" in tool_types
                                   and self.tool_server is not None
                                   and self.tool_server.has_tool("python"))
        sys_msg = get_system_message(
            reasoning_effort=reasoning_effort,
            browser_description=self.tool_server.get_tool_description(
                "browser")
            if enable_browser and self.tool_server is not None else None,
            python_description=self.tool_server.get_tool_description(
                "python") if enable_code_interpreter
            and self.tool_server is not None else None,
        )
        messages.append(sys_msg)
        dev_msg = get_developer_message(request.instructions,
                                        request.tools)
        messages.append(dev_msg)
    else:
        # Continue the previous conversation.
        # FIXME(woosuk): Currently, request params like reasoning and
        # instructions are ignored.
        prev_msgs = self.msg_store[prev_response.id]
        # Remove the previous chain-of-thoughts if there is a new "final"
        # message. Note that this also removes these messages from the
        # msg_store.
        if len(prev_msgs) > 0:
            last_msg = prev_msgs[-1]
            assert isinstance(last_msg, OpenAIHarmonyMessage)
            if last_msg.channel == "final":
                prev_final_msg_idx = -1
                for i in range(len(prev_msgs) - 2, -1, -1):
                    prev_msg_i = prev_msgs[i]
                    assert isinstance(prev_msg_i, OpenAIHarmonyMessage)
                    if prev_msg_i.channel == "final":
                        prev_final_msg_idx = i
                        break
                recent_turn_msgs = prev_msgs[prev_final_msg_idx + 1:]
                del prev_msgs[prev_final_msg_idx + 1:]
                for msg in recent_turn_msgs:
                    assert isinstance(msg, OpenAIHarmonyMessage)
                    if msg.channel != "analysis":
                        prev_msgs.append(msg)
        messages.extend(prev_msgs)
    # Append the new input.
    # Reponses API supports simple text inputs without chat format.
    if isinstance(request.input, str):
        messages.append(get_user_message(request.input))
    else:
        if prev_response is not None:
            prev_outputs = copy(prev_response.output)
        else:
            prev_outputs = []
        for response_msg in request.input:
            messages.append(
                parse_response_input(response_msg, prev_outputs))
            # User passes in a a tool call request and its output. We need
            # to add the tool call request to prev_outputs so that the
            # parse_response_input can find the tool call request when
            # parsing the tool call output.
            if isinstance(response_msg, ResponseFunctionToolCall):
                prev_outputs.append(response_msg)
    return messages

_create_response_logprobs

_create_response_logprobs(
    token_ids: Sequence[int],
    logprobs: Optional[SampleLogprobs],
    tokenizer: AnyTokenizer,
    top_logprobs: Optional[int] = None,
) -> list[Logprob]
Source code in vllm/entrypoints/openai/serving_responses.py
def _create_response_logprobs(
        self,
        token_ids: Sequence[int],
        logprobs: Optional[SampleLogprobs],
        tokenizer: AnyTokenizer,
        top_logprobs: Optional[int] = None) -> list[Logprob]:
    assert logprobs is not None, "logprobs must be provided"
    assert len(token_ids) == len(logprobs), (
        "token_ids and logprobs.token_ids must have the same length")
    out = []
    for i, token_id in enumerate(token_ids):
        logprob = logprobs[i]
        token_logprob = logprob[token_id]
        text = token_logprob.decoded_token if token_logprob.decoded_token \
            is not None else tokenizer.decode([token_id])
        out.append(
            Logprob(
                token=text,
                logprob=max(token_logprob.logprob, -9999.0),
                bytes=list(text.encode("utf-8", errors="replace")),
                top_logprobs=self._topk_logprobs(logprob,
                                                 top_logprobs=top_logprobs,
                                                 tokenizer=tokenizer)
                if top_logprobs else [],
            ))
    return out

_make_invalid_id_error

_make_invalid_id_error(response_id: str) -> ErrorResponse
Source code in vllm/entrypoints/openai/serving_responses.py
def _make_invalid_id_error(self, response_id: str) -> ErrorResponse:
    return self.create_error_response(
        err_type="invalid_request_error",
        message=(f"Invalid 'response_id': '{response_id}'. "
                 "Expected an ID that begins with 'resp'."),
    )

_make_not_found_error

_make_not_found_error(response_id: str) -> ErrorResponse
Source code in vllm/entrypoints/openai/serving_responses.py
def _make_not_found_error(self, response_id: str) -> ErrorResponse:
    return self.create_error_response(
        err_type="invalid_request_error",
        message=f"Response with id '{response_id}' not found.",
        status_code=HTTPStatus.NOT_FOUND,
    )

_make_request async

_make_request(
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse],
    tokenizer: AnyTokenizer,
)
Source code in vllm/entrypoints/openai/serving_responses.py
async def _make_request(
    self,
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse],
    tokenizer: AnyTokenizer,
):
    if len(request.tools) > 0:
        raise NotImplementedError(
            "Tool use is not supported in Responses API without Harmony")
    # Construct the input messages.
    messages = self._construct_input_messages(request, prev_response)
    _, request_prompts, engine_prompts = await self._preprocess_chat(
        request,
        tokenizer,
        messages,
        chat_template=self.chat_template,
        chat_template_content_format=self.chat_template_content_format,
    )
    return messages, request_prompts, engine_prompts

_make_request_with_harmony

_make_request_with_harmony(
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse],
)
Source code in vllm/entrypoints/openai/serving_responses.py
def _make_request_with_harmony(
    self,
    request: ResponsesRequest,
    prev_response: Optional[ResponsesResponse],
):
    if request.tool_choice != "auto":
        raise NotImplementedError(
            "Only 'auto' tool_choice is supported in "
            "response API with Harmony")
    messages = self._construct_input_messages_with_harmony(
        request, prev_response)
    prompt_token_ids = render_for_completion(messages)
    engine_prompt = EngineTokensPrompt(prompt_token_ids=prompt_token_ids)

    # Add cache_salt if provided in the request
    if request.cache_salt is not None:
        engine_prompt["cache_salt"] = request.cache_salt

    return messages, [prompt_token_ids], [engine_prompt]

_make_response_output_items

_make_response_output_items(
    request: ResponsesRequest,
    final_output: CompletionOutput,
    tokenizer: AnyTokenizer,
) -> list[ResponseOutputItem]
Source code in vllm/entrypoints/openai/serving_responses.py
def _make_response_output_items(
    self,
    request: ResponsesRequest,
    final_output: CompletionOutput,
    tokenizer: AnyTokenizer,
) -> list[ResponseOutputItem]:
    if self.reasoning_parser:
        try:
            reasoning_parser = self.reasoning_parser(tokenizer)
        except RuntimeError as e:
            logger.exception("Error in reasoning parser creation.")
            raise e

        reasoning_content, content = (
            reasoning_parser.extract_reasoning_content(final_output.text,
                                                       request=request))
    else:
        reasoning_content = None
        content = final_output.text

    # Log complete response if output logging is enabled
    if self.enable_log_outputs and self.request_logger:
        output_text = ""
        if content:
            output_text = content
        elif reasoning_content:
            output_text = f"[reasoning: {reasoning_content}]"

        if output_text:
            self.request_logger.log_outputs(
                request_id=request.request_id,
                outputs=output_text,
                output_token_ids=final_output.token_ids,
                finish_reason=final_output.finish_reason,
                is_streaming=False,
                delta=False,
            )

    output = []
    if reasoning_content:
        reasoning_item = ResponseReasoningItem(
            id=f"rs_{random_uuid()}",
            summary=[],
            type="reasoning",
            content=[
                ResponseReasoningTextContent(text=reasoning_content,
                                             type="reasoning_text")
            ],
            status=None,  # NOTE: Only the last output item has status.
        )
        output.append(reasoning_item)
    if content:
        output_text = ResponseOutputText(
            text=content,
            annotations=[],  # TODO
            type="output_text",
            logprobs=self._create_response_logprobs(
                token_ids=final_output.token_ids,
                logprobs=final_output.logprobs,
                tokenizer=tokenizer,
                top_logprobs=request.top_logprobs,
            ) if request.is_include_output_logprobs() else None,
        )
        message = ResponseOutputMessage(
            id=f"msg_{random_uuid()}",
            content=[output_text],
            role="assistant",
            status="completed",
            type="message",
        )
        output.append(message)
    return output

_make_response_output_items_with_harmony

_make_response_output_items_with_harmony(
    context: HarmonyContext,
) -> list[ResponseOutputItem]
Source code in vllm/entrypoints/openai/serving_responses.py
def _make_response_output_items_with_harmony(
    self,
    context: HarmonyContext,
) -> list[ResponseOutputItem]:
    output_items = []
    num_init_messages = context.num_init_messages
    for msg in context.messages[num_init_messages:]:
        output_items.extend(parse_output_message(msg))
    # Handle the generation stopped in the middle (if any).
    last_items = parse_remaining_state(context.parser)
    if last_items:
        output_items.extend(last_items)
    return output_items

_make_store_not_supported_error

_make_store_not_supported_error() -> ErrorResponse
Source code in vllm/entrypoints/openai/serving_responses.py
def _make_store_not_supported_error(self) -> ErrorResponse:
    return self.create_error_response(
        err_type="invalid_request_error",
        message=("`store=True` (default) is not supported. Please set "
                 "`store=False` in Responses API or set "
                 "`VLLM_ENABLE_RESPONSES_API_STORE=1` in the env var when "
                 "starting the vLLM server."),
        status_code=HTTPStatus.BAD_REQUEST,
    )

_run_background_request async

_run_background_request(
    request: ResponsesRequest, *args, **kwargs
)
Source code in vllm/entrypoints/openai/serving_responses.py
async def _run_background_request(
    self,
    request: ResponsesRequest,
    *args,
    **kwargs,
):
    try:
        response = await self.responses_full_generator(
            request, *args, **kwargs)
    except Exception as e:
        logger.exception("Background request failed for %s",
                         request.request_id)
        response = self.create_error_response(str(e))

    if isinstance(response, ErrorResponse):
        # If the request has failed, update the status to "failed".
        response_id = request.request_id
        async with self.response_store_lock:
            stored_response = self.response_store.get(response_id)
            assert stored_response is not None
            if stored_response.status not in ("completed", "cancelled"):
                stored_response.status = "failed"

_topk_logprobs

_topk_logprobs(
    logprobs: dict[int, Logprob],
    top_logprobs: int,
    tokenizer: AnyTokenizer,
) -> list[LogprobTopLogprob]

Returns the top-k logprobs from the logprobs dictionary.

Source code in vllm/entrypoints/openai/serving_responses.py
def _topk_logprobs(self, logprobs: dict[int,
                                        SampleLogprob], top_logprobs: int,
                   tokenizer: AnyTokenizer) -> list[LogprobTopLogprob]:
    """Returns the top-k logprobs from the logprobs dictionary."""
    out = []
    for i, (token_id, _logprob) in enumerate(logprobs.items()):
        if i >= top_logprobs:
            break
        text = _logprob.decoded_token if _logprob.decoded_token \
            is not None else tokenizer.decode([token_id])
        out.append(
            LogprobTopLogprob(
                token=text,
                logprob=max(_logprob.logprob, -9999.0),
                bytes=list(text.encode("utf-8", errors="replace")),
            ))
    return out

cancel_responses async

cancel_responses(
    response_id: str,
) -> Union[ErrorResponse, ResponsesResponse]
Source code in vllm/entrypoints/openai/serving_responses.py
async def cancel_responses(
    self,
    response_id: str,
) -> Union[ErrorResponse, ResponsesResponse]:
    if not response_id.startswith("resp_"):
        return self._make_invalid_id_error(response_id)

    async with self.response_store_lock:
        response = self.response_store.get(response_id)
        if response is None:
            return self._make_not_found_error(response_id)

        prev_status = response.status
        if prev_status not in ("queued", "in_progress"):
            return self.create_error_response(
                err_type="invalid_request_error",
                message="Cannot cancel a synchronous response.",
            )

        # Update the status to "cancelled".
        response.status = "cancelled"

    # Abort the request.
    if (task := self.background_tasks.get(response_id)):
        task.cancel()
        try:
            await task
        except asyncio.CancelledError:
            logger.exception("Background task for %s was cancelled",
                             response_id)
    return response

create_responses async

create_responses(
    request: ResponsesRequest,
    raw_request: Optional[Request] = None,
) -> Union[
    AsyncGenerator[str, None],
    ResponsesResponse,
    ErrorResponse,
]
Source code in vllm/entrypoints/openai/serving_responses.py
async def create_responses(
    self,
    request: ResponsesRequest,
    raw_request: Optional[Request] = None,
) -> Union[AsyncGenerator[str, None], ResponsesResponse, ErrorResponse]:
    error_check_ret = await self._check_model(request)
    if error_check_ret is not None:
        logger.error("Error with model %s", error_check_ret)
        return error_check_ret

    # If the engine is dead, raise the engine's DEAD_ERROR.
    # This is required for the streaming case, where we return a
    # success status before we actually start generating text :).
    if self.engine_client.errored:
        raise self.engine_client.dead_error

    if request.store and not self.enable_store:
        if request.background:
            return self.create_error_response(
                err_type="invalid_request_error",
                message=(
                    "This vLLM engine does not support `store=True` and "
                    "therefore does not support the background mode. To "
                    "enable these features, set the environment variable "
                    "`VLLM_ENABLE_RESPONSES_API_STORE=1` when launching "
                    "the vLLM server."),
                status_code=HTTPStatus.BAD_REQUEST,
            )
        # Disable the store option.
        # NOTE(woosuk): Although returning an error is possible, we opted
        # to implicitly disable store and process the request anyway, as
        # we assume most users do not intend to actually store the response
        # (i.e., their request's `store=True` just because it's the default
        # value).
        request.store = False
    if self.use_harmony and request.is_include_output_logprobs():
        return self.create_error_response(
            err_type="invalid_request_error",
            message="logprobs are not supported with gpt-oss models",
            status_code=HTTPStatus.BAD_REQUEST,
        )

    # Handle the previous response ID.
    prev_response_id = request.previous_response_id
    if prev_response_id is not None:
        if not prev_response_id.startswith("resp_"):
            return self._make_invalid_id_error(prev_response_id)
        async with self.response_store_lock:
            prev_response = self.response_store.get(prev_response_id)
        if prev_response is None:
            return self._make_not_found_error(prev_response_id)
    else:
        prev_response = None

    try:
        lora_request = self._maybe_get_adapters(request)
        model_name = self._get_model_name(request.model, lora_request)
        tokenizer = await self.engine_client.get_tokenizer(lora_request)

        if self.use_harmony:
            messages, request_prompts, engine_prompts = (
                self._make_request_with_harmony(request, prev_response))
        else:
            messages, request_prompts, engine_prompts = (
                await self._make_request(request, prev_response,
                                         tokenizer))

    except (ValueError, TypeError, RuntimeError, jinja2.TemplateError,
            NotImplementedError) as e:
        logger.exception("Error in preprocessing prompt inputs")
        return self.create_error_response(f"{e} {e.__cause__}")

    request_metadata = RequestResponseMetadata(
        request_id=request.request_id)
    if raw_request:
        raw_request.state.request_metadata = request_metadata

    if self.tool_server is not None and isinstance(
            self.tool_server, MCPToolServer
    ) and (request.background or request.stream) and request.tools and any(
            tool.type in ["web_search_preview", "code_interpreter"]
            for tool in request.tools):
        return self.create_error_response(
            "MCP tool server is not supported in background mode and "
            "streaming mode")

    # Schedule the request and get the result generator.
    generators: list[AsyncGenerator[ConversationContext, None]] = []

    builtin_tool_list: list[str] = []
    if self.use_harmony and self.tool_server is not None:
        if self.tool_server.has_tool("browser"):
            builtin_tool_list.append("browser")
        if self.tool_server.has_tool("python"):
            builtin_tool_list.append("python")
    async with AsyncExitStack() as exit_stack:
        try:
            if self.tool_server is not None:
                # TODO: initialize tool sessions lazily when the session
                # is actually used.
                tool_session_ctxs: dict[str, Any] = {
                    tool_name:
                    exit_stack.enter_async_context(
                        self.tool_server.new_session(tool_name))
                    for tool_name in builtin_tool_list
                }
                tool_sessions = {}
                for tool_name in builtin_tool_list:
                    tool_sessions[tool_name] = (
                        await tool_session_ctxs[tool_name])
            else:
                assert len(builtin_tool_list) == 0
                tool_sessions = {}
            for i, engine_prompt in enumerate(engine_prompts):
                default_max_tokens = self.max_model_len - len(
                    engine_prompt["prompt_token_ids"])
                sampling_params = request.to_sampling_params(
                    default_max_tokens, self.default_sampling_params)

                trace_headers = (None if raw_request is None else await
                                 self._get_trace_headers(
                                     raw_request.headers))

                context: ConversationContext
                if self.use_harmony:
                    if request.stream:
                        context = StreamingHarmonyContext(
                            messages, tool_sessions)
                    else:
                        context = HarmonyContext(messages, tool_sessions)
                else:
                    context = SimpleContext()
                generator = self._generate_with_builtin_tools(
                    request_id=request.request_id,
                    request_prompt=request_prompts[i],
                    engine_prompt=engine_prompt,
                    sampling_params=sampling_params,
                    context=context,
                    lora_request=lora_request,
                    priority=request.priority,
                    trace_headers=trace_headers,
                )
                generators.append(generator)
        except ValueError as e:
            # TODO: Use a vllm-specific Validation Error
            return self.create_error_response(str(e))

        assert len(generators) == 1
        result_generator, = generators

        # Store the input messages.
        if request.store:
            self.msg_store[request.request_id] = messages

        if request.background:
            created_time = int(time.time())
            response = ResponsesResponse.from_request(
                request,
                sampling_params,
                model_name=model_name,
                created_time=created_time,
                output=[],
                status="queued",
                usage=None,
            )
            async with self.response_store_lock:
                self.response_store[response.id] = response

            # Run the request in the background.
            task = asyncio.create_task(
                self._run_background_request(
                    request,
                    sampling_params,
                    result_generator,
                    context,
                    model_name,
                    tokenizer,
                    request_metadata,
                    created_time,
                ),
                name=f"create_{response.id}",
            )

            # For cleanup.
            response_id = response.id
            self.background_tasks[response_id] = task
            task.add_done_callback(
                lambda _: self.background_tasks.pop(response_id, None))
            return response

        if request.stream:
            return self.responses_stream_generator(
                request,
                sampling_params,
                result_generator,
                context,
                model_name,
                tokenizer,
                request_metadata,
            )

        try:
            return await self.responses_full_generator(
                request,
                sampling_params,
                result_generator,
                context,
                model_name,
                tokenizer,
                request_metadata,
            )
        except Exception as e:
            return self.create_error_response(str(e))
    return self.create_error_response("Should not reach here")

responses_full_generator async

responses_full_generator(
    request: ResponsesRequest,
    sampling_params: SamplingParams,
    result_generator: AsyncIterator[ConversationContext],
    context: ConversationContext,
    model_name: str,
    tokenizer: AnyTokenizer,
    request_metadata: RequestResponseMetadata,
    created_time: Optional[int] = None,
) -> Union[ErrorResponse, ResponsesResponse]
Source code in vllm/entrypoints/openai/serving_responses.py
async def responses_full_generator(
    self,
    request: ResponsesRequest,
    sampling_params: SamplingParams,
    result_generator: AsyncIterator[ConversationContext],
    context: ConversationContext,
    model_name: str,
    tokenizer: AnyTokenizer,
    request_metadata: RequestResponseMetadata,
    created_time: Optional[int] = None,
) -> Union[ErrorResponse, ResponsesResponse]:
    if created_time is None:
        created_time = int(time.time())

    try:
        async for _ in result_generator:
            pass
    except asyncio.CancelledError:
        return self.create_error_response("Client disconnected")
    except ValueError as e:
        # TODO: Use a vllm-specific Validation Error
        return self.create_error_response(str(e))

    if self.use_harmony:
        assert isinstance(context, HarmonyContext)
        output = self._make_response_output_items_with_harmony(context)
        # TODO: these are all 0 for now!
        num_prompt_tokens = context.num_prompt_tokens
        num_generated_tokens = context.num_output_tokens
        num_cached_tokens = context.num_cached_tokens
        num_reasoning_tokens = context.num_reasoning_tokens
    else:
        assert isinstance(context, SimpleContext)
        final_res = context.last_output
        assert final_res is not None
        assert len(final_res.outputs) == 1
        final_output = final_res.outputs[0]

        output = self._make_response_output_items(request, final_output,
                                                  tokenizer)

        # Calculate usage.
        assert final_res.prompt_token_ids is not None
        num_prompt_tokens = len(final_res.prompt_token_ids)
        num_generated_tokens = len(final_output.token_ids)
        num_cached_tokens = final_res.num_cached_tokens
        num_reasoning_tokens = 0

    usage = ResponseUsage(
        input_tokens=num_prompt_tokens,
        output_tokens=num_generated_tokens,
        total_tokens=num_prompt_tokens + num_generated_tokens,
        input_tokens_details=InputTokensDetails(
            cached_tokens=num_cached_tokens),
        output_tokens_details=OutputTokensDetails(
            reasoning_tokens=num_reasoning_tokens),
    )
    response = ResponsesResponse.from_request(
        request,
        sampling_params,
        model_name=model_name,
        created_time=created_time,
        output=output,
        status="completed",
        usage=usage,
    )

    if request.store:
        async with self.response_store_lock:
            stored_response = self.response_store.get(response.id)
            # If the response is already cancelled, don't update it.
            if (stored_response is None
                    or stored_response.status != "cancelled"):
                self.response_store[response.id] = response
    return response

responses_stream_generator async

responses_stream_generator(
    request: ResponsesRequest,
    sampling_params: SamplingParams,
    result_generator: AsyncIterator[
        Optional[ConversationContext]
    ],
    context: ConversationContext,
    model_name: str,
    tokenizer: AnyTokenizer,
    request_metadata: RequestResponseMetadata,
    created_time: Optional[int] = None,
) -> AsyncGenerator[str, None]
Source code in vllm/entrypoints/openai/serving_responses.py
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async def responses_stream_generator(
    self,
    request: ResponsesRequest,
    sampling_params: SamplingParams,
    result_generator: AsyncIterator[Optional[ConversationContext]],
    context: ConversationContext,
    model_name: str,
    tokenizer: AnyTokenizer,
    request_metadata: RequestResponseMetadata,
    created_time: Optional[int] = None,
) -> AsyncGenerator[str, None]:
    # TODO:
    # 1. Handle disconnect

    if not isinstance(context, StreamingHarmonyContext):
        raise NotImplementedError(
            "Streaming is not supported for responses API without Harmony."
        )

    created_time = created_time or int(time.time())

    sequence_number = 0

    def _send_event(event: BaseModel):
        nonlocal sequence_number
        # Set sequence_number if the event has this attribute
        if hasattr(event, 'sequence_number'):
            event.sequence_number = sequence_number
        sequence_number += 1
        # Get event type from the event's type field if it exists
        event_type = getattr(event, 'type', 'unknown')
        return (f"event: {event_type}\n"
                f"data: {event.model_dump_json(indent=None)}\n\n")

    current_content_index = 0  # FIXME: this number is never changed
    current_output_index = 0
    current_item_id = ""  # FIXME: this number is never changed
    sent_output_item_added = False

    initial_response = ResponsesResponse.from_request(
        request,
        sampling_params,
        model_name=model_name,
        created_time=created_time,
        output=[],
        status="in_progress",
        usage=None,
    ).model_dump()
    yield _send_event(
        ResponseCreatedEvent(
            type="response.created",
            sequence_number=-1,
            response=initial_response,
        ))
    yield _send_event(
        ResponseInProgressEvent(
            type="response.in_progress",
            sequence_number=-1,
            response=initial_response,
        ))

    async for ctx in result_generator:

        assert isinstance(ctx, StreamingHarmonyContext)

        if ctx.is_expecting_start():
            current_output_index += 1
            sent_output_item_added = False

            if len(ctx.parser.messages) > 0:
                previous_item = ctx.parser.messages[-1]
                if previous_item.recipient is not None:
                    # Deal with tool call here
                    pass
                elif previous_item.channel == "analysis":
                    reasoning_item = ResponseReasoningItem(
                        type="reasoning",
                        content=[
                            ResponseReasoningTextContent(
                                text=previous_item.content[0].text,
                                type="reasoning_text",
                            ),
                        ],
                        status="completed",
                        id=current_item_id,
                        summary=[],
                    )
                    yield _send_event(
                        ResponseReasoningTextDoneEvent(
                            type="response.reasoning_text.done",
                            item_id=current_item_id,
                            sequence_number=-1,
                            output_index=current_output_index,
                            content_index=current_content_index,
                            text=previous_item.content[0].text,
                        ))
                    yield _send_event(
                        ResponseOutputItemDoneEvent(
                            type="response.output_item.done",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=reasoning_item,
                        ))
                elif previous_item.channel == "final":
                    text_content = ResponseOutputText(
                        type="output_text",
                        text=previous_item.content[0].text,
                        annotations=[],
                    )
                    yield _send_event(
                        openai_responses_types.ResponseTextDoneEvent(
                            type="response.output_text.done",
                            sequence_number=-1,
                            output_index=current_output_index,
                            content_index=current_content_index,
                            text=previous_item.content[0].text,
                            logprobs=[],
                            item_id=current_item_id,
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseContentPartDoneEvent(
                            type="response.content_part.done",
                            sequence_number=-1,
                            item_id=current_item_id,
                            output_index=current_output_index,
                            content_index=current_content_index,
                            part=text_content,
                        ))
                    yield _send_event(
                        openai_responses_types.ResponseOutputItemDoneEvent(
                            type="response.output_item.done",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=ResponseOutputMessage(
                                id=current_item_id,
                                type="message",
                                role="assistant",
                                content=[text_content],
                                status="completed",
                            ),
                        ))

        if ctx.parser.last_content_delta:
            if (ctx.parser.current_channel == "final"
                    and ctx.parser.current_recipient is None):
                if not sent_output_item_added:
                    sent_output_item_added = True
                    yield _send_event(
                        openai_responses_types.
                        ResponseOutputItemAddedEvent(
                            type="response.output_item.added",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=openai_responses_types.
                            ResponseOutputMessage(
                                id=current_item_id,
                                type="message",
                                role="assistant",
                                content=[],
                                status="in_progress",
                            ),
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseContentPartAddedEvent(
                            type="response.content_part.added",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                            content_index=current_content_index,
                            part=openai_responses_types.ResponseOutputText(
                                type="output_text",
                                text="",
                                annotations=[],
                                logprobs=[],
                            ),
                        ))
                yield _send_event(
                    openai_responses_types.ResponseTextDeltaEvent(
                        type="response.output_text.delta",
                        sequence_number=-1,
                        content_index=current_content_index,
                        output_index=current_output_index,
                        item_id=current_item_id,
                        delta=ctx.parser.last_content_delta,
                        # TODO, use logprobs from ctx.last_request_output
                        logprobs=[],
                    ))
            elif (ctx.parser.current_channel == "analysis"
                  and ctx.parser.current_recipient is None):
                if not sent_output_item_added:
                    sent_output_item_added = True
                    yield _send_event(
                        openai_responses_types.
                        ResponseOutputItemAddedEvent(
                            type="response.output_item.added",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=openai_responses_types.
                            ResponseReasoningItem(
                                type="reasoning",
                                id=current_item_id,
                                summary=[],
                                status="in_progress",
                            ),
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseContentPartAddedEvent(
                            type="response.content_part.added",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                            content_index=current_content_index,
                            part=openai_responses_types.ResponseOutputText(
                                type="output_text",
                                text="",
                                annotations=[],
                                logprobs=[],
                            ),
                        ))
                yield _send_event(
                    ResponseReasoningTextDeltaEvent(
                        type="response.reasoning_text.delta",
                        item_id=current_item_id,
                        output_index=current_output_index,
                        content_index=current_content_index,
                        delta=ctx.parser.last_content_delta,
                        sequence_number=-1,
                    ))
            # built-in tools will be triggered on the analysis channel
            # However, occasionally built-in tools will
            # still be output to commentary.
            elif (ctx.parser.current_channel == "commentary"
                  or ctx.parser.current_channel == "analysis"
                  ) and ctx.parser.current_recipient == "python":
                if not sent_output_item_added:
                    sent_output_item_added = True
                    yield _send_event(
                        openai_responses_types.
                        ResponseOutputItemAddedEvent(
                            type="response.output_item.added",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item=openai_responses_types.
                            ResponseCodeInterpreterToolCallParam(
                                type="code_interpreter_call",
                                id=current_item_id,
                                code=None,
                                container_id="auto",
                                outputs=None,
                                status="in_progress",
                            ),
                        ))
                    yield _send_event(
                        openai_responses_types.
                        ResponseCodeInterpreterCallInProgressEvent(
                            type=
                            "response.code_interpreter_call.in_progress",
                            sequence_number=-1,
                            output_index=current_output_index,
                            item_id=current_item_id,
                        ))
                yield _send_event(
                    openai_responses_types.
                    ResponseCodeInterpreterCallCodeDeltaEvent(
                        type="response.code_interpreter_call_code.delta",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item_id=current_item_id,
                        delta=ctx.parser.last_content_delta,
                    ))
        if ctx.is_assistant_action_turn() and len(ctx.parser.messages) > 0:
            previous_item = ctx.parser.messages[-1]
            if (self.tool_server is not None
                    and self.tool_server.has_tool("browser")
                    and previous_item.recipient is not None
                    and previous_item.recipient.startswith("browser.")):
                function_name = previous_item.recipient[len("browser."):]
                action = None
                parsed_args = json.loads(previous_item.content[0].text)
                if function_name == "search":
                    action = (openai_responses_types.
                              response_function_web_search.ActionSearch(
                                  type="search",
                                  query=parsed_args["query"],
                              ))
                elif function_name == "open":
                    action = (
                        openai_responses_types.
                        response_function_web_search.ActionOpenPage(
                            type="open_page",
                            # TODO: translate to url
                            url=f"cursor:{parsed_args.get('cursor', '')}",
                        ))
                elif function_name == "find":
                    action = (
                        openai_responses_types.
                        response_function_web_search.ActionFind(
                            type="find",
                            pattern=parsed_args["pattern"],
                            # TODO: translate to url
                            url=f"cursor:{parsed_args.get('cursor', '')}",
                        ))
                else:
                    raise ValueError(
                        f"Unknown function name: {function_name}")

                yield _send_event(
                    openai_responses_types.ResponseOutputItemAddedEvent(
                        type="response.output_item.added",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item=openai_responses_types.
                        response_function_web_search.
                        ResponseFunctionWebSearch(
                            # TODO: generate a unique id for web search call
                            type="web_search_call",
                            id=current_item_id,
                            action=action,
                            status="in_progress",
                        ),
                    ))
                yield _send_event(
                    openai_responses_types.
                    ResponseWebSearchCallInProgressEvent(
                        type="response.web_search_call.in_progress",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item_id=current_item_id,
                    ))
                yield _send_event(
                    openai_responses_types.
                    ResponseWebSearchCallSearchingEvent(
                        type="response.web_search_call.searching",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item_id=current_item_id,
                    ))

                # enqueue
                yield _send_event(
                    openai_responses_types.
                    ResponseWebSearchCallCompletedEvent(
                        type="response.web_search_call.completed",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item_id=current_item_id,
                    ))
                yield _send_event(
                    openai_responses_types.ResponseOutputItemDoneEvent(
                        type="response.output_item.done",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item=openai_responses_types.
                        ResponseFunctionWebSearch(
                            type="web_search_call",
                            id=current_item_id,
                            action=action,
                            status="completed",
                        ),
                    ))

            if (self.tool_server is not None
                    and self.tool_server.has_tool("python")
                    and previous_item.recipient is not None
                    and previous_item.recipient.startswith("python")):
                yield _send_event(
                    openai_responses_types.
                    ResponseCodeInterpreterCallCodeDoneEvent(
                        type="response.code_interpreter_call_code.done",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item_id=current_item_id,
                        code=previous_item.content[0].text,
                    ))
                yield _send_event(
                    openai_responses_types.
                    ResponseCodeInterpreterCallInterpretingEvent(
                        type="response.code_interpreter_call.interpreting",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item_id=current_item_id,
                    ))
                yield _send_event(
                    openai_responses_types.
                    ResponseCodeInterpreterCallCompletedEvent(
                        type="response.code_interpreter_call.completed",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item_id=current_item_id,
                    ))
                yield _send_event(
                    openai_responses_types.ResponseOutputItemDoneEvent(
                        type="response.output_item.done",
                        sequence_number=-1,
                        output_index=current_output_index,
                        item=openai_responses_types.
                        ResponseCodeInterpreterToolCallParam(
                            type="code_interpreter_call",
                            id=current_item_id,
                            code=previous_item.content[0].text,
                            container_id="auto",
                            # TODO: add outputs here
                            outputs=[],
                            status="completed",
                        ),
                    ))

    async def empty_async_generator():
        # A hack to trick Python to think this is a generator but in fact
        # it immediately returns.
        if False:
            yield

    final_response = await self.responses_full_generator(
        request,
        sampling_params,
        empty_async_generator(),
        context,
        model_name,
        tokenizer,
        request_metadata,
        created_time=created_time,
    )
    yield _send_event(
        openai_responses_types.ResponseCompletedEvent(
            type="response.completed",
            sequence_number=-1,
            response=final_response.model_dump(),
        ))

retrieve_responses async

retrieve_responses(
    response_id: str,
) -> Union[ErrorResponse, ResponsesResponse]
Source code in vllm/entrypoints/openai/serving_responses.py
async def retrieve_responses(
    self,
    response_id: str,
) -> Union[ErrorResponse, ResponsesResponse]:
    if not response_id.startswith("resp_"):
        return self._make_invalid_id_error(response_id)

    async with self.response_store_lock:
        response = self.response_store.get(response_id)

    if response is None:
        return self._make_not_found_error(response_id)
    return response