adk web doesn't find agent

[ukaer]

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Describe the bug
Running adk web my_agent loads ui but shows "Warning: No agents found in current folder." and agent is not available in dropdown. Running adk run my_agent works fine, running code in init.py loads things fine as well.

To Reproduce
Please share a minimal code and data to reproduce your problem.
Steps to reproduce the behavior:

1. in my_agent/ foder have these two files:

init.py:
from .agent import root_agent

agent.py:

from google.adk.agents import Agent

print("bbb")

# This is a minimal agent definition. Does this work?
root_agent = Agent(
    name="basic_test_agent",
    model="gemini-2.5-flash",
    instruction="Respond to all inquiries with 'Hello world'."
)

2. Follow steps to create venv, activate and install google-adk
3. From parent directory of my_agent, I run: adk web my_agent
4. Open browser to http://127.0.0.1:8000/
5. UI shows but no agent found. Also no errors when running with --verbose of --log_level DEBUG
6. running adk run my_agent works fine and am able to interact as expected.

Expected behavior
Web UI should show my agent and allow me to interact with it.

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Windows 11
• Python version(python -V): Python 3.13.7
• ADK version(pip show google-adk): 1.15.1

Model Information:

• Are you using LiteLLM: No
• Which model is being used(e.g. gemini-2.5-pro): gemini-2.0-flash

Additional context
Add any other context about the problem here.

[ukaer]

Also tried with adk create new_agent, same result.

[ejfn]

Try __init__.py?
Or you don't even need __init__.py, just do
adk web ./, the path containing the my_agent?

[AlexFierro9]

can you change init.py to __ init __.py? Also have you tried running just 'adk web'? we are using this at work and it's oddly stupid.

[rcodestoo]

Running just 'adk web' actually worked

[AlexFierro9]

I'm glad it's sorted

[ukaer]

Thanks, and my bad - I wrote init.py but the file was correctly named init.py

starting in the agent dir with adk web ./ results in the same issue. Also tried removing the init.py and had same results - UI is available but "Warning: No agents found in current folder." and no agent selectable from left dropdown (but works fine w/ adk run)

[ukaer]

Ah ok looks like I had probably written it right but markdown is eating the underscores and needs to be escaped __init__.py

[boyangsvl]

moving to discussions as it seems to be a set up issue rather than an ADK bug.

[adk-bot]

Response from ADK Answering Agent (experimental, answer may be inaccurate)

TLDR: The issue is likely due to either running on an unsupported Python version (3.13.7) or a known problem with adk web's auto-reloader on Windows. Please try using the --no-reload flag or downgrading to a supported Python version like 3.12.

Hello! Based on the information you provided and documentation, here are a couple of potential solutions to this issue. The problem likely stems from the environment you are running in.

1. Use the --no-reload Flag

The adk web command's auto-reload feature can sometimes cause issues on Windows. The documentation suggests a specific workaround for this.

Please try running the command with the --no-reload flag:

adk web my_agent --no-reload

This disables the file watcher but may resolve the agent discovery problem on your system. [1]

2. Use a Supported Python Version

ADK currently supports Python versions 3.9 through 3.12. You are using Python 3.13.7, which is very new and likely not yet fully supported by ADK or its underlying dependencies. This can lead to unexpected behavior, especially with complex features like the adk web server.

We recommend downgrading your Python version to 3.12. You can manage multiple Python versions using tools like pyenv or by downloading an official installer. After installing a supported version, please create a new virtual environment, reinstall google-adk, and try running the command again.

This is the more robust solution and will ensure you are in a tested and supported environment.

Let us know if either of these solutions works for you!

[1] https://google.github.io/adk-docs/tools/mcp-tools/

[rcodestoo]

the first method did not work. I am using Python 3.11.7

[bupretijc]

Following. i am also running into the same issue.

[ukaer]

Trying with --no-reload results in the same issue, so did running with Python 3.12.10 (uninstalled all versions of Python, removed venv and rebuilt from scratch).

[leviexner]

@boyangsvl consider moving this back to issues, I see this issue as well. Notably adk run works while adk web does not work in the same directory.