mcp-client-session-manag-creating-and-closing-multiple-mcp-clientsession-ob-1ab0d566

THEN To avoid the error, close the ClientSession objects in reverse order of creation. For example, if session1 is created first then session2, close session2 before session1. Alternatively, use a single AsyncExitStack to manage both sessions to prevent cancel scope conflicts.

# Correct order to avoid cancel scope error
async def sessions():
    async with AsyncExitStack() as stack1:
        read1, write1 = await stack1.enter_async_context(stdio_client(params1))
        session1 = await stack1.enter_async_context(ClientSession(read1, write1))
        await session1.initialize()
        
    async with AsyncExitStack() as stack2:
        read2, write2 = await stack2.enter_async_context(sse_client(url=params2.url))
        session2 = await stack2.enter_async_context(ClientSession(read2, write2))
        await session2.initialize()
        
    # stack2 closes before stack1 automatically via context manager (reverse order)