Timeout for initializing MCP client

[alexmojaki]

Demo script:

import asyncio

from pydantic_ai import Agent
from pydantic_ai.mcp import MCPServerStdio

server = MCPServerStdio('python', args=[], timeout=100)  # will wait this many seconds
agent = Agent('openai:gpt-4o', mcp_servers=[server])


async def main():
    async with agent.run_mcp_servers():
        ...


asyncio.run(main())

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[DouweM]

@alexmojaki Thanks! I just merged #1716 which changes the timeout property from a float to a timedelta, because that's what the MCP library now requires on its new StreamableHTTP transport. Can you please update this to use timedeltas as well?

[jlaneve]

heads up that when I'm running a stateless remote MCP server, this PR breaks the connection. specifically, if I comment out these 2 lines, it begins working again

I haven't had time to fully look into this, but I just get this log and then it hangs:

Connecting to StreamableHTTP endpoint: http://xxx

I wonder if it's related to modelcontextprotocol/python-sdk#815

[DouweM]

@jlaneve Strange, can you please file a new issue for that bug?

[alexmojaki]

This made me notice #1843, but that's probably not the issue.