MCPServerAdapter does not have transport as an argument [Streamable-http]

[Pratik_Kumar]

Hi folks been trying to run a crew using tools from a MCP server with Streamable-Http as a transport. Although works well enough with the same server when i change the transport of server to SSE without giving any transport argument in my ServerParam. Also this code is in crew template using CrewBase. Here’s the code

    from crewai import Agent, Crew, Process, Task
from crewai.project import CrewBase, agent, crew, task
from crewai.agents.agent_builder.base_agent import BaseAgent
from typing import List
import os
from crewai import Agent, Crew, Process, Task,LLM
from crewai.project import CrewBase, agent, crew, task
from crewai.agents.agent_builder.base_agent import BaseAgent
from typing import List, Optional,Dict,Any,Literal
from pydantic import BaseModel
from crewai_tools import MCPServerAdapter
from dotenv import load_dotenv
load_dotenv()

token="jfdnksah"
# Initialize the LLM using environment variables
llm = LLM(
    model="azure/gpt-4o"
)

@CrewBase
class Crew():
    """ crew"""
    agents_config="config/agents.yaml"
    task_config="config/tasks.yaml"

    def __init__(self):
        super().__init__()
        self._start_mcp()

    def _start_mcp(self): 
        server_params = {
            "url": "http://localhost:80o0/mcp/",
            "transport": "streamable-http",
           "headers": {
                    "Authorization": f"Bearer {token}"
            }
        }
        self.mcp_adapter = MCPServerAdapter(server_params)
        self.mcp_tools = self.mcp_adapter.tools
        for tool in self.mcp_tools:
            print(f"Loaded tool: {tool.name}")

    @agent
    def snow_manager(self) -> Agent:
        return Agent(
            config=self.agents_config['manager'], # type: ignore[index]
            verbose=True,
            llm=llm,
            tools=self.mcp_tools
        )

    @task
    def research_task(self) -> Task:
        return Task(
            config=self.tasks_config['task'],
        )


    @crew
    def crew(self) -> Crew:
        """Creates the SnowCrew crew"""
        # To learn how to add knowledge sources to your crew, check out the documentation:
        # https://docs.crewai.com/concepts/knowledge#what-is-knowledge

        return Crew(
            agents=self.agents, # Automatically created by the @agent decorator
            tasks=self.tasks, # Automatically created by the @task decorator
            process=Process.sequential,
            verbose=True,
            chat_llm=llm
        )

The error i am recieving is

Exception in thread Thread-3 (_run_loop):
Traceback (most recent call last):
  File "C:\Users\850081290\AppData\Local\Programs\Python\Python311\Lib\threading.py", line 1045, in _bootstrap_inner
    self.run()
  File "C:\Users\850081290\AppData\Local\Programs\Python\Python311\Lib\threading.py", line 982, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\850081290\Documents\New folder\gen1\Lib\site-packages\mcpadapt\core.py", line 216, in _run_loop
    self.loop.run_until_complete(self.task)
  File "C:\Users\850081290\AppData\Local\Programs\Python\Python311\Lib\asyncio\base_events.py", line 654, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "C:\Users\850081290\Documents\New folder\gen1\Lib\site-packages\mcpadapt\core.py", line 206, in setup
    connections = [
                  ^
  File "C:\Users\850081290\Documents\New folder\gen1\Lib\site-packages\mcpadapt\core.py", line 207, in <listcomp>
    await stack.enter_async_context(mcptools(params))
  File "C:\Users\850081290\AppData\Local\Programs\Python\Python311\Lib\contextlib.py", line 650, in enter_async_context
    result = await _enter(cm)
             ^^^^^^^^^^^^^^^^
  File "C:\Users\850081290\AppData\Local\Programs\Python\Python311\Lib\contextlib.py", line 210, in __aenter__
    return await anext(self.gen)
           ^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\850081290\Documents\New folder\gen1\Lib\site-packages\mcpadapt\core.py", line 98, in mcptools
    client = sse_client(**serverparams)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\850081290\AppData\Local\Programs\Python\Python311\Lib\contextlib.py", line 334, in helper
    return _AsyncGeneratorContextManager(func, args, kwds)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\850081290\AppData\Local\Programs\Python\Python311\Lib\contextlib.py", line 105, in __init__
    self.gen = func(*args, **kwds)
               ^^^^^^^^^^^^^^^^^^^
TypeError: sse_client() got an unexpected keyword argument 'transport'

Everything in this code works fine with sse as transport without giving any transport argument but as soon as the transport is defined as streamable-http in server param its throws an error. Also gives 400 Bad Request if no transport with streamble-http server url given. Please help.

[Pratik_Kumar]

@maxmoura i think you can only help

[maxmoura]

1. Your url likely shouldn’t be http://localhost:80o0/mcp/ (using the letter “o” instead of a zero in the port number).
2. It seems you’re using the Manual Connection Lifecycle. I’d recommend following the official documentation’s example step-by-step, ensuring you call mcp_server_adapter.start() and explicitly handle mcp_server_adapter.stop().