[gpt-oss] add demo tool server (#22393)

Signed-off-by: Chen Zhang <zhangch99@outlook.com>

vllm/entrypoints/openai/api_server.py

@@ -92,6 +92,7 @@ from vllm.entrypoints.openai.serving_tokenization import (
 from vllm.entrypoints.openai.serving_transcription import (
     OpenAIServingTranscription, OpenAIServingTranslation)
 from vllm.entrypoints.openai.tool_parsers import ToolParserManager
+from vllm.entrypoints.tool_server import DemoToolServer, ToolServer
 from vllm.entrypoints.utils import (cli_env_setup, load_aware_call,
                                     log_non_default_args, with_cancellation)
 from vllm.logger import init_logger
@@ -1620,6 +1621,11 @@ async def init_app_state(
                     "This discrepancy may lead to performance degradation.",
                     resolved_chat_template, args.model)
 
+    if args.tool_server == "demo":
+        tool_server: Optional[ToolServer] = DemoToolServer()
+    else:
+        tool_server = None
+
     # Merge default_mm_loras into the static lora_modules
     default_mm_loras = (vllm_config.lora_config.default_mm_loras
                         if vllm_config.lora_config is not None else {})
@@ -1654,6 +1660,7 @@ async def init_app_state(
         return_tokens_as_token_ids=args.return_tokens_as_token_ids,
         enable_auto_tools=args.enable_auto_tool_choice,
         tool_parser=args.tool_call_parser,
+        tool_server=tool_server,
         reasoning_parser=args.reasoning_parser,
         enable_prompt_tokens_details=args.enable_prompt_tokens_details,
         enable_force_include_usage=args.enable_force_include_usage,

vllm/entrypoints/openai/cli_args.py

@@ -147,6 +147,10 @@ schema. Example: `[{"type": "text", "text": "Hello world!"}]`"""
     """Special the tool parser plugin write to parse the model-generated tool
     into OpenAI API format, the name register in this plugin can be used in
     `--tool-call-parser`."""
+    tool_server: Optional[str] = None
+    """Comma-separated list of host:port pairs (IPv4, IPv6, or hostname).
+    Examples: 127.0.0.1:8000, [::1]:8000, localhost:1234. Or `demo` for demo
+    purpose."""
     log_config_file: Optional[str] = envs.VLLM_LOGGING_CONFIG_PATH
     """Path to logging config JSON file for both vllm and uvicorn"""
     max_log_len: Optional[int] = None

vllm/entrypoints/openai/serving_responses.py

@@ -29,6 +29,7 @@ from vllm.entrypoints.openai.protocol import (ErrorResponse,
 # yapf: enable
 from vllm.entrypoints.openai.serving_engine import OpenAIServing
 from vllm.entrypoints.openai.serving_models import OpenAIServingModels
+from vllm.entrypoints.tool_server import ToolServer
 from vllm.logger import init_logger
 from vllm.reasoning import ReasoningParser, ReasoningParserManager
 from vllm.sampling_params import SamplingParams
@@ -53,6 +54,7 @@ class OpenAIServingResponses(OpenAIServing):
         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,
     ) -> None:
@@ -114,6 +116,8 @@ class OpenAIServingResponses(OpenAIServing):
 
         self.background_tasks: dict[str, asyncio.Task] = {}
 
+        self.tool_server = tool_server
+
     async def create_responses(
         self,
         request: ResponsesRequest,

vllm/entrypoints/tool_server.py

+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+from abc import ABC, abstractmethod
+from contextlib import AbstractAsyncContextManager, asynccontextmanager
+from typing import Any, Optional
+
+from openai_harmony import ToolNamespaceConfig
+
+from vllm.entrypoints.tool import HarmonyBrowserTool, HarmonyPythonTool, Tool
+from vllm.logger import init_logger
+
+logger = init_logger(__name__)
+
+
+class ToolServer(ABC):
+
+    @abstractmethod
+    def has_tool(self, tool_name: str) -> bool:
+        """
+        Return True if the tool is supported, False otherwise.
+        """
+        pass
+
+    @abstractmethod
+    def get_tool_description(self,
+                             tool_name: str) -> Optional[ToolNamespaceConfig]:
+        """
+        Return the tool description for the given tool name.
+        If the tool is not supported, return None.
+        """
+        pass
+
+    @abstractmethod
+    def new_session(self, tool_name: str) -> AbstractAsyncContextManager[Any]:
+        """
+        Create a session for the tool.
+        """
+        ...
+
+
+class DemoToolServer(ToolServer):
+
+    def __init__(self):
+        self.tools: dict[str, Tool] = {}
+        browser_tool = HarmonyBrowserTool()
+        if browser_tool.enabled:
+            self.tools["browser"] = browser_tool
+        python_tool = HarmonyPythonTool()
+        if python_tool.enabled:
+            self.tools["python"] = python_tool
+        logger.info("DemoToolServer initialized with tools: %s",
+                    list(self.tools.keys()))
+
+    def has_tool(self, tool_name: str) -> bool:
+        return tool_name in self.tools
+
+    def get_tool_description(self,
+                             tool_name: str) -> Optional[ToolNamespaceConfig]:
+        if tool_name not in self.tools:
+            return None
+        if tool_name == "browser":
+            return ToolNamespaceConfig.browser()
+        elif tool_name == "python":
+            return ToolNamespaceConfig.python()
+        else:
+            raise ValueError(f"Unknown tool {tool_name}")
+
+    @asynccontextmanager
+    async def new_session(self, tool_name: str):
+        yield self.tools[tool_name]