Files
SmartVoyage/demo/mcp/stdio_agent.py

78 lines
2.8 KiB
Python
Raw Normal View History

2026-03-19 19:28:48 +08:00
import os
import sys
sys.path.append(os.path.join(os.path.dirname(__file__), "../../.."))
import asyncio
from langchain_mcp_adapters.tools import load_mcp_tools
from langchain_openai import ChatOpenAI
from langchain.agents import create_tool_calling_agent, AgentExecutor
from langchain_core.prompts import ChatPromptTemplate
from mcp import ClientSession, StdioServerParameters
from mcp.client.stdio import stdio_client
from conf import settings
# 创建模型
llm = ChatOpenAI(
base_url=settings.base_url,
api_key=settings.api_key,
model=settings.model_name,
temperature=0.1
)
# 配置mcp服务器脚本路径
server_script = r".\stdio_server.py"
# 配置mcp服务器启动参数
server_params = StdioServerParameters(
command="python" if server_script.endswith(".py") else "node",
args=[server_script],
)
# 定义mcp客户端
mcp_client = None
# 主要的异步函数run_agent
async def run_agent():
global mcp_client
# 启动 MCP server并通过标准输入输出建立异步连接。
async with stdio_client(server_params) as (read, write):
# 使用读写通道创建 MCP 会话。
async with ClientSession(read, write) as session:
# 初始化会话
await session.initialize()
# 动态创建一个临时类 MCPClientHolder把 session 放进去。这样就可以在函数外部通过 mcp_client.session 调用 MCP 工具
mcp_client = type("MCPClientHolder", (), {"session": session})()
# 从 session 自动获取 MCP server 提供的工具列表
tools = await load_mcp_tools(session)
# print(f"tools-->{tools}")
# 创建prompt模板
prompt_template = ChatPromptTemplate.from_messages([
("system", "你是一个乐于助人的助手,能够调用工具回答用户问题。"),
("human", "{input}"),
("placeholder", "{agent_scratchpad}"),
])
# 构建工具调用代理
agent = create_tool_calling_agent(llm, tools, prompt_template)
# 创建代理执行器
agent_executor = AgentExecutor(agent=agent, tools=tools, verbose=True)
# 代理调用
print("MCP客户端启动输入'quit'退出")
while True:
# 接收用户查询
query = input("\nQuery: ").strip()
if query.lower() == "quit":
break
# 发送用户查询给代理,并打印
try:
response = await agent_executor.ainvoke({"input": query})
print(f"response-->{response}")
except Exception:
print("解析有问题")
return
if __name__ == "__main__":
asyncio.run(run_agent())