Agent working in local but not when deployed to Cloud Run, with error "AttributeError: 'coroutine' object has no attribute 'status'"

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**Describe the bug**
I am trying to deploy an agent to Cloud Run, it works fine locally using adk web to test it, but when deployed to Cloud Run (using adk deploy cloud run) it fails with error at first interaction (saying "Hi" or something in the web chat interface).

The agent must connect to a MCP server (using toolbox_core) already deployed and running on the same Cloud Run, with or without authentication.
Local instance could connect fine to the MCP server and working fine with it.

The error stack is the following:
`
INFO: 169.254.169.126:41924 - "POST /run_sse HTTP/1.1" 200 OK
Error in event_generator: 'coroutine' object has no attribute 'status'
(most recent call last): File "/home/myuser/.local/lib/python3.12/site-packages/google/adk/cli/fast_api.py", line 805, in event_generator runner = await _get_runner_async(req.app_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/google/adk/cli/fast_api.py", line 978, in _get_runner_async
root_agent = await _get_root_agent_async(app_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/google/adk/cli/fast_api.py", line 963, in _get_root_agent_async
agent_module = importlib.import_module(app_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/importlib/__init__.py", line 90, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "", line 1387, in _gcd_import
File "", line 1360, in _find_and_load
File "", line 1331, in _find_and_load_unlocked
File "", line 935, in _load_unlocked
File "", line 999, in exec_module
File "", line 488, in _call_with_frames_removed
File "/app/webravo-agent1/__init__.py", line 1, in
from . import agent
File "/app/webravo-agent1/agent.py", line 32, in
agent_toolset = toolbox_client.load_toolset("merchants-toolset")
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/toolbox_core/sync_client.py", line 154, in load_toolset
async_tools = asyncio.run_coroutine_threadsafe(coro, self.__loop).result()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/concurrent/futures/_base.py", line 456, in result
return self.__get_result()
^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/concurrent/futures/_base.py", line 401, in __get_result
raise self._exception
File "/home/myuser/.local/lib/python3.12/site-packages/toolbox_core/client.py", line 264, in load_toolset
header_name: await resolve_value(original_headers[header_name])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/toolbox_core/utils.py", line 143, in resolve_value
return await source()
^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/toolbox_core/auth_methods.py", line 50, in aget_google_id_token
await creds.refresh(_aiohttp_requests.Request())
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/google/auth/compute_engine/credentials.py", line 126, in refresh
self._retrieve_info(request)
File "/home/myuser/.local/lib/python3.12/site-packages/google/auth/compute_engine/credentials.py", line 99, in _retrieve_info
info = _metadata.get_service_account_info(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/google/auth/compute_engine/_metadata.py", line 342, in get_service_account_info
return get(request, path, params={"recursive": "true"})
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/myuser/.local/lib/python3.12/site-packages/google/auth/compute_engine/_metadata.py", line 212, in get
if response.status in transport.DEFAULT_RETRYABLE_STATUS_CODES:
^^^^^^^^^^^^^^^
AttributeError: 'coroutine' object has no attribute 'status'
/home/myuser/.local/lib/python3.12/site-packages/google/adk/cli/fast_api.py:819: RuntimeWarning: coroutine 'Request.__call__' was never awaited
yield f'data: {{"error": "{str(e)}"}}\n\n'
RuntimeWarning: Enable tracemalloc to get the object allocation traceback
Unclosed client session
client_session:
`
**Expected behavior**
Expected to run as in local environment

**Desktop (please complete the following information):**
- OS: Google Cloud Run
- Python version(python -V): 3.12
- ADK version(pip show google-adk): 1.0.0

**Additional context**
I've already tried:
- Try "cloud run deploy" instead of "adk deploy cloud run" with custom Dockerfile - same error
- Try deploying in another region (both europe-west2 and us-central1, the same of the gemini model) - same error
- Try to allow unauthenticated access to both agent and mcp server cloud run services - same error

My Agent code (names offuscated):
`
from google.adk.agents import Agent
from google.adk.runners import Runner
from google.adk.sessions import InMemorySessionService
from google.adk.artifacts.in_memory_artifact_service import InMemoryArtifactService
from toolbox_core import ToolboxSyncClient, auth_methods
import os
import datetime

os.environ['GOOGLE_GENAI_USE_VERTEXAI'] = 'True'
os.environ['GOOGLE_CLOUD_PROJECT'] = 'my-project'
os.environ['GOOGLE_CLOUD_LOCATION'] = 'us-central1'

auth_token_provider = auth_methods.aget_google_id_token # can also use sync method
toolbox_client = ToolboxSyncClient(
"https://my-toolbox-xxxxxxxxxx.us-central1.run.app",
client_headers={"Authorization": auth_token_provider},
)

agent_toolset = toolbox_client.load_toolset("my-toolset")

prompt = """
You're a helpful assistant.
"""

root_agent = Agent(
model='gemini-2.5-flash-preview-05-20',
name='my_test_agent',
description='A helpful AI assistant',
instruction=prompt,
tools=agent_toolset,
)
`