The quickstart tutorial has an error in the __init__.py file documentation.

[seanmwalker]

Describe the bug

When following the quickstart tutorial, there is a bug in the init.py where the variable for 'agent' needs to be 'root_agent' to match the agent.py file.

This has been noted in the adk-python issues, though it is actually an issue in the documentation.

google/adk-python#73

To Reproduce

Steps to reproduce the behavior:

1. Follow the tutorial, and try to run the application.
2. Note the stack trace when you try to ask the chat bot anything.
3. See error "AttributeError: module 'multi_tool_agent' has no attribute 'agent'" in the console output.

Expected behavior

With the correct variable name, the agent will respond appropriately.

Screenshots

If applicable, add screenshots to help explain your problem.

Versions

• OS: Windows
• ADK version: 0.1.0
• Python version: 3.12.3

Additional context

N/A

[seanmwalker]

#42 Should help with this.

[AshleyHenry15]

@koverholt - will this require a documentation change or should will the docs "work as expected" once the bug is resolved?

[lavinigam-gcp]

Thank you for raising this. We are checking if this is already been resolved.

[Sita04]

Hi @seanmwalker , thank you for filing such a detailed bug report!

This is a very subtle point about how the ADK's command-line tools work.
The code in the Quickstart's __init__.py file is

from . import agent

When you use the standard adk web or adk run commands, the ADK's runner is designed to automatically inspect the package you provide (multi_tool_agent). It successfully finds the agent module within that package and then looks inside that module to find the root_agent variable. Because the runner performs this deeper search, the Quickstart works as intended without any changes.

But when you run it from a custom python script — change the line to from .agent import root_agent. This approach exposes the root_agent variable at the top level of the package. This is what is happening in your environment to cause the AttributeError.

We'll use your feedback to see how we can improve the documentation to avoid this confusion in the future. As the Quickstart code is functional for its stated purpose, I will go ahead and close this issue