From c94ffcc8722ee7e83a45ca97ee9a57d5e3d199a0 Mon Sep 17 00:00:00 2001 From: Rohan Mehta Date: Wed, 26 Mar 2025 12:49:39 -0400 Subject: [PATCH] MCP example for SSE Simple example with a local SSE server. --- examples/mcp/filesystem_example/README.md | 2 +- examples/mcp/git_example/README.md | 5 +- examples/mcp/git_example/main.py | 8 +-- examples/mcp/sse_example/README.md | 13 ++++ examples/mcp/sse_example/main.py | 83 +++++++++++++++++++++++ examples/mcp/sse_example/server.py | 33 +++++++++ 6 files changed, 135 insertions(+), 9 deletions(-) create mode 100644 examples/mcp/sse_example/README.md create mode 100644 examples/mcp/sse_example/main.py create mode 100644 examples/mcp/sse_example/server.py diff --git a/examples/mcp/filesystem_example/README.md b/examples/mcp/filesystem_example/README.md index 1b6b1837..83183fb4 100644 --- a/examples/mcp/filesystem_example/README.md +++ b/examples/mcp/filesystem_example/README.md @@ -10,7 +10,7 @@ uv run python python examples/mcp/filesystem_example/main.py ## Details -The example uses the `MCPServerStdio` class from `agents`, with the command: +The example uses the `MCPServerStdio` class from `agents.mcp`, with the command: ```bash npx -y "@modelcontextprotocol/server-filesystem" diff --git a/examples/mcp/git_example/README.md b/examples/mcp/git_example/README.md index 35ff7cde..6a809afa 100644 --- a/examples/mcp/git_example/README.md +++ b/examples/mcp/git_example/README.md @@ -10,16 +10,17 @@ uv run python examples/mcp/git_example/main.py ## Details -The example uses the `MCPServerStdio` class from `agents`, with the command: +The example uses the `MCPServerStdio` class from `agents.mcp`, with the command: ```bash uvx mcp-server-git ``` + Prior to running the agent, the user is prompted to provide a local directory path to their git repo. Using that, the Agent can invoke Git MCP tools like `git_log` to inspect the git commit log. Under the hood: 1. The server is spun up in a subprocess, and exposes a bunch of tools like `git_log()` 2. We add the server instance to the Agent via `mcp_agents`. -3. Each time the agent runs, we call out to the MCP server to fetch the list of tools via `server.list_tools()`. The result is cached. +3. Each time the agent runs, we call out to the MCP server to fetch the list of tools via `server.list_tools()`. The result is cached. 4. If the LLM chooses to use an MCP tool, we call the MCP server to run the tool via `server.run_tool()`. diff --git a/examples/mcp/git_example/main.py b/examples/mcp/git_example/main.py index cfc15108..ab229e85 100644 --- a/examples/mcp/git_example/main.py +++ b/examples/mcp/git_example/main.py @@ -30,12 +30,8 @@ async def main(): directory_path = input("Please enter the path to the git repository: ") async with MCPServerStdio( - params={ - "command": "uvx", - "args": [ - "mcp-server-git" - ] - } + cache_tools_list=True, # Cache the tools list, for demonstration + params={"command": "uvx", "args": ["mcp-server-git"]}, ) as server: with trace(workflow_name="MCP Git Example"): await run(server, directory_path) diff --git a/examples/mcp/sse_example/README.md b/examples/mcp/sse_example/README.md new file mode 100644 index 00000000..605c2cc9 --- /dev/null +++ b/examples/mcp/sse_example/README.md @@ -0,0 +1,13 @@ +# MCP SSE Example + +This example uses a local SSE server in [server.py](server.py). + +Run the example via: + +``` +uv run python python examples/mcp/sse_example/main.py +``` + +## Details + +The example uses the `MCPServerSse` class from `agents.mcp`. The server runs in a sub-process at `https://localhost:8000/sse`. diff --git a/examples/mcp/sse_example/main.py b/examples/mcp/sse_example/main.py new file mode 100644 index 00000000..024b087e --- /dev/null +++ b/examples/mcp/sse_example/main.py @@ -0,0 +1,83 @@ +import asyncio +import os +import shutil +import subprocess +import time +from typing import Any + +from agents import Agent, Runner, gen_trace_id, trace +from agents.mcp import MCPServer, MCPServerSse +from agents.model_settings import ModelSettings + + +async def run(mcp_server: MCPServer): + agent = Agent( + name="Assistant", + instructions="Use the tools to answer the questions.", + mcp_servers=[mcp_server], + model_settings=ModelSettings(tool_choice="required"), + ) + + # Use the `add` tool to add two numbers + message = "Add these numbers: 7 and 22." + print(f"Running: {message}") + result = await Runner.run(starting_agent=agent, input=message) + print(result.final_output) + + # Run the `get_weather` tool + message = "What's the weather in Tokyo?" + print(f"\n\nRunning: {message}") + result = await Runner.run(starting_agent=agent, input=message) + print(result.final_output) + + # Run the `get_secret_word` tool + message = "What's the secret word?" + print(f"\n\nRunning: {message}") + result = await Runner.run(starting_agent=agent, input=message) + print(result.final_output) + + +async def main(): + async with MCPServerSse( + name="SSE Python Server", + params={ + "url": "http://localhost:8000/sse", + }, + ) as server: + trace_id = gen_trace_id() + with trace(workflow_name="SSE Example", trace_id=trace_id): + print(f"View trace: https://platform.openai.com/traces/{trace_id}\n") + await run(server) + + +if __name__ == "__main__": + # Let's make sure the user has uv installed + if not shutil.which("uv"): + raise RuntimeError( + "uv is not installed. Please install it: https://docs.astral.sh/uv/getting-started/installation/" + ) + + # We'll run the SSE server in a subprocess. Usually this would be a remote server, but for this + # demo, we'll run it locally at http://localhost:8000/sse + process: subprocess.Popen[Any] | None = None + try: + this_dir = os.path.dirname(os.path.abspath(__file__)) + server_file = os.path.join(this_dir, "server.py") + + print("Starting SSE server at http://localhost:8000/sse ...") + + # Run `uv run server.py` to start the SSE server + process = subprocess.Popen(["uv", "run", server_file]) + # Give it 3 seconds to start + time.sleep(3) + + print("SSE server started. Running example...\n\n") + except Exception as e: + print(f"Error starting SSE server: {e}") + exit(1) + + try: + asyncio.run(main()) + finally: + if process: + process.terminate() diff --git a/examples/mcp/sse_example/server.py b/examples/mcp/sse_example/server.py new file mode 100644 index 00000000..df364aa3 --- /dev/null +++ b/examples/mcp/sse_example/server.py @@ -0,0 +1,33 @@ +import random + +import requests +from mcp.server.fastmcp import FastMCP + +# Create server +mcp = FastMCP("Echo Server") + + +@mcp.tool() +def add(a: int, b: int) -> int: + """Add two numbers""" + print(f"[debug-server] add({a}, {b})") + return a + b + + +@mcp.tool() +def get_secret_word() -> str: + print("[debug-server] get_secret_word()") + return random.choice(["apple", "banana", "cherry"]) + + +@mcp.tool() +def get_current_weather(city: str) -> str: + print(f"[debug-server] get_current_weather({city})") + + endpoint = "https://wttr.in" + response = requests.get(f"{endpoint}/{city}") + return response.text + + +if __name__ == "__main__": + mcp.run(transport="sse")