ADK web not working, but runs in terminal

[dominicdev]

I got a working agent with notion mcp, it runs without a problem in teminal but getting error running in adk web, the error show up when starting to chat with the agent

here's is the log for error

2025-05-23 20:28:33,851 - INFO - envs.py:47 - Loaded .env file for main_agent at D:\Documents\Python\git\agent system\agent_notion_tool\main_agent\.env 2025-05-23 20:28:33,866 - ERROR - fast_api.py:637 - Error in event_generator: Traceback (most recent call last): File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\cli\fast_api.py", line 625, in event_generator runner = await _get_runner_async(req.app_name) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\cli\fast_api.py", line 796, in _get_runner_async root_agent = await _get_root_agent_async(app_name) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\cli\fast_api.py", line 773, in _get_root_agent_async agent_module = importlib.import_module(app_name) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\importlib\__init__.py", line 90, in import_module return _bootstrap._gcd_import(name[level:], package, level) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "<frozen importlib._bootstrap>", line 1387, in _gcd_import File "<frozen importlib._bootstrap>", line 1360, in _find_and_load File "<frozen importlib._bootstrap>", line 1331, in _find_and_load_unlocked File "<frozen importlib._bootstrap>", line 935, in _load_unlocked File "<frozen importlib._bootstrap_external>", line 995, in exec_module File "<frozen importlib._bootstrap>", line 488, in _call_with_frames_removed File "D:\Documents\Python\git\agent system\agent_notion_tool\main_agent\__init__.py", line 1, in <module> from . import agent File "D:\Documents\Python\git\agent system\agent_notion_tool\main_agent\agent.py", line 51, in <module> root_agent = asyncio.run(build_agent())[0] ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\nest_asyncio.py", line 30, in run return loop.run_until_complete(task) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\nest_asyncio.py", line 98, in run_until_complete return f.result() ^^^^^^^^^^ File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\asyncio\futures.py", line 203, in result raise self._exception.with_traceback(self._exception_tb) File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\asyncio\tasks.py", line 314, in __step_run_and_handle_result result = coro.send(None) ^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\main_agent\agent.py", line 27, in build_agent notion_tools, stack = await MCPToolset.from_server( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\tools\mcp_tool\mcp_toolset.py", line 223, in from_server await async_exit_stack.enter_async_context(toolset) File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\contextlib.py", line 659, in enter_async_context result = await _enter(cm) ^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\tools\mcp_tool\mcp_toolset.py", line 258, in __aenter__ raise e File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\tools\mcp_tool\mcp_toolset.py", line 255, in __aenter__ await self._initialize() File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\tools\mcp_tool\mcp_toolset.py", line 229, in _initialize self.session = await self.session_manager.create_session() ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\tools\mcp_tool\mcp_session_manager.py", line 132, in create_session return await MCPSessionManager.initialize_session( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\google\adk\tools\mcp_tool\mcp_session_manager.py", line 173, in initialize_session transports = await exit_stack.enter_async_context(client) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\contextlib.py", line 659, in enter_async_context result = await _enter(cm) ^^^^^^^^^^^^^^^^ File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\contextlib.py", line 210, in __aenter__ return await anext(self.gen) ^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\mcp\client\stdio.py", line 104, in stdio_client process = await anyio.open_process( ^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\anyio\_core\_subprocesses.py", line 190, in open_process return await get_async_backend().open_process( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "D:\Documents\Python\git\agent system\agent_notion_tool\.venv\Lib\site-packages\anyio\_backends\_asyncio.py", line 2561, in open_process process = await asyncio.create_subprocess_exec( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\asyncio\subprocess.py", line 224, in create_subprocess_exec transport, protocol = await loop.subprocess_exec( ^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\asyncio\base_events.py", line 1743, in subprocess_exec transport = await self._make_subprocess_transport( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Admin\AppData\Roaming\uv\python\cpython-3.12.7-windows-x86_64-none\Lib\asyncio\base_events.py", line 524, in _make_subprocess_transport raise NotImplementedError NotImplementedError

here is also my code

`
from dotenv import load_dotenv
import nest_asyncio
import os, json, asyncio
from contextlib import AsyncExitStack

from google.adk.agents.llm_agent import LlmAgent
from google.adk.tools.mcp_tool.mcp_toolset import (
MCPToolset, StdioServerParameters, SseServerParams
)

MODEL = "gemini-2.5-flash-preview-04-17" # Or "gemini-1.5-pro-latest" for more power

nest_asyncio.apply()

load_dotenv()

NOTION_API_KEY = os.getenv("NOTION_API_KEY")
NOTION_HEADERS = json.dumps({
"Authorization": f"Bearer {NOTION_API_KEY}",
"Notion-Version": "2022-06-28"
})

async def build_agent():
notion_tools, stack = await MCPToolset.from_server(
connection_params=StdioServerParameters(
command="npx.cmd",
args=["-y", "@notionhq/notion-mcp-server"],
env={"OPENAPI_MCP_HEADERS": NOTION_HEADERS},
)
)

print(f"total tools {len(notion_tools)}")

agent = LlmAgent(
    model="gemini-2.0-flash",
    name="notion_helper",
    instruction=(
        "You are my workspace assistant. "
        "Use the provided tools to read, search, comment on, "
        "or create Notion pages. Ask clarifying questions when unsure."
    ),
    tools=notion_tools,
)
return agent, stack

root_agent = asyncio.run(build_agent())[0]
`

[seanzhou1023]

looks like you are using old adk versions. we have changed he MCPToolset interface in 1.0.0 + could you try the new version ?

something like below :

agent = LlmAgent(
model="gemini-2.0-flash",
name="notion_helper",
instruction=(
"You are my workspace assistant. "
"Use the provided tools to read, search, comment on, "
"or create Notion pages. Ask clarifying questions when unsure."
),
tools=[
MCPToolset(
connection_params=StdioServerParameters(
command="npx",
args=["-y", "@notionhq/notion-mcp-server"],
env={"OPENAPI_MCP_HEADERS": NOTION_HEADERS},
)
)
],
)