> ## Documentation Index
> Fetch the complete documentation index at: https://agentcontrol-abhi-agent-control-auth-contract-docs.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Google ADK Decorator

> Use Agent Control's @control() decorator for tool protection inside a Google ADK app.

This example shows how to use Agent Control's `@control()` decorator inside a Google ADK app.

Use this example if you want ADK as the host framework but prefer Agent Control's decorator model for tool protection. If you want the default framework-native path, use [/examples/google-adk-plugin](/examples/google-adk-plugin).

## What It Demonstrates

* `@control()` on ADK tool functions
* automatic step registration from decorated functions
* pre-tool blocking for restricted cities
* post-tool output filtering for synthetic unsafe output
* optional sdk-local execution without changing the agent code

## Prerequisites

1. Start the Agent Control server from the repo root:

   ```bash theme={null}
   make server-run
   ```

2. Install the example dependencies:

   ```bash theme={null}
   cd examples/google_adk_decorator
   uv pip install -e . --upgrade
   ```

3. Set your Google API key:

   ```bash theme={null}
   export GOOGLE_API_KEY="your-key-here"
   ```

4. Optional environment variables:

   ```bash theme={null}
   export AGENT_CONTROL_URL=http://localhost:8000
   export GOOGLE_MODEL=gemini-2.5-flash
   ```

## Setup

Default server execution:

```bash theme={null}
cd examples/google_adk_decorator
uv run python setup_controls.py
```

Optional sdk-local execution:

```bash theme={null}
cd examples/google_adk_decorator
uv run python setup_controls.py --execution sdk
```

The example code does not change between modes. The only difference is where the controls run:

* `server` - evaluation happens on the Agent Control server
* `sdk` - evaluation happens locally in the Python SDK after the controls are fetched

The setup script creates namespace-scoped controls for this example:

* `adk-decorator-block-restricted-cities`
* `adk-decorator-block-internal-contact-output`

## Run

```bash theme={null}
cd examples/google_adk_decorator
uv run adk run my_agent
```

## Suggested Scenarios

Safe request:

```text theme={null}
What time is it in London?
```

Restricted city blocked before the tool call:

```text theme={null}
What is the weather in Pyongyang?
```

Synthetic unsafe tool output blocked after the tool call:

```text theme={null}
What time is it in Testville?
```

## Files

* `setup_controls.py` - creates the decorator example controls
* `my_agent/agent.py` - ADK app that wraps tools with `@control()`
* `.env.example` - environment variables for local runs

## Notes

* This example focuses on tool-level protection only.
* The guarded tool implementations are marked with tool metadata before `@control()` runs. That is needed because the current Python SDK infers `tool` vs `llm` from function metadata at decoration time.
* If you want the recommended packaged integration, use [/examples/google-adk-plugin](/examples/google-adk-plugin).
* If you want the ADK-native callback integration pattern, use [/examples/google-adk-callbacks](/examples/google-adk-callbacks).

## Source Code

View the complete example with all scripts and setup instructions:

[`Google ADK Decorator Example`](https://github.com/agentcontrol/agent-control/tree/main/examples/google_adk_decorator)