adk-python/CONTRIBUTING.md

# How to contribute

We'd love to accept your patches and contributions to this project.

## Table of Contents

- [Before you begin](#before-you-begin)  
  - [Sign our Contributor License Agreement](#sign-our-contributor-license-agreement)  
  - [Review our community guidelines](#review-our-community-guidelines)
- [Contribution workflow](#contribution-workflow)  
  - [Finding Issues to Work On](#finding-issues-to-work-on)  
  - [Requirement for PRs](#requirement-for-prs)  
  - [Large or Complex Changes](#large-or-complex-changes)  
  - [Testing Requirements](#testing-requirements)  
  - [Unit Tests](#unit-tests)  
  - [End-to-End (E2E) Tests](#manual-end-to-end-e2e-tests)  
  - [Documentation](#documentation)  
  - [Development Setup](#development-setup)  
- [Code reviews](#code-reviews)

  
## Before you begin

### Sign our Contributor License Agreement

Contributions to this project must be accompanied by a
[Contributor License Agreement](https://cla.developers.google.com/about) (CLA).
You (or your employer) retain the copyright to your contribution; this simply
gives us permission to use and redistribute your contributions as part of the
project.

If you or your current employer have already signed the Google CLA (even if it
was for a different project), you probably don't need to do it again.

Visit <https://cla.developers.google.com/> to see your current agreements or to
sign a new one.

### Review our community guidelines

This project follows
[Google's Open Source Community Guidelines](https://opensource.google/conduct/).

## Contribution workflow

### Finding Issues to Work On

- Browse issues labeled **`good first issue`** (newcomer-friendly) or **`help wanted`** (general contributions).  
- For other issues, please kindly ask before contributing to avoid duplication.


### Requirement for PRs

- All PRs, other than small documentation or typo fixes, should have a Issue assoicated. If not, please create one. 
- Small, focused PRs. Keep changes minimal—one concern per PR.
- For bug fixes or features, please provide logs or screenshot after the fix is applied to help reviewers better understand the fix.
- Please include a `testing plan` section in your PR to talk about how you will test. This will save time for PR review. See `Testing Requirements` section for more details.

### Large or Complex Changes
For substantial features or architectural revisions:

- Open an Issue First: Outline your proposal, including design considerations and impact.
- Gather Feedback: Discuss with maintainers and the community to ensure alignment and avoid duplicate work

### Testing Requirements

To maintain code quality and prevent regressions, all code changes must include comprehensive tests and verifiable end-to-end (E2E) evidence.


#### Unit Tests

Please add or update unit tests for your change. Please include a summary of passed `pytest` results.

Requirements for unit tests:

- **Coverage:** Cover new features, edge cases, error conditions, and typical use cases.  
- **Location:** Add or update tests under `tests/unittests/`, following existing naming conventions (e.g., `test_<module>_<feature>.py`).  
- **Framework:** Use `pytest`. Tests should be:  
  - Fast and isolated.  
  - Written clearly with descriptive names.  
  - Free of external dependencies (use mocks or fixtures as needed).  
- **Quality:** Aim for high readability and maintainability; include docstrings or comments for complex scenarios.

#### Manual End-to-End (E2E) Tests

Manual E2E tests ensure integrated flows work as intended. Your tests should cover all scenarios. Sometimes, it's also good to ensure relevant functionality is not impacted.

Depending on your change:

- **ADK Web:**  
  - Use the `adk web` to verify functionality.  
  - Capture and attach relevant screenshots demonstrating the UI/UX changes or outputs.  
  - Label screenshots clearly in your PR description.

- **Runner:**
  - Provide the testing setup. For example, the agent definition, and the runner setup.
  - Execute the `runner` tool to reproduce workflows.  
  - Include the command used and console output showing test results.  
  - Highlight sections of the log that directly relate to your change.

### Documentation

For any changes that impact user-facing documentation (guides, API reference, tutorials), please open a PR in the [adk-docs](https://github.com/google/adk-docs) repository to update relevant part before or alongside your code PR.

### Development Setup
1.  **Clone the repository:**

    ```shell
    git clone git@github.com:google/adk-python.git
    cd adk-python
    ```
2.  **Create and activate a virtual environment:**

    ```shell
    python -m venv .venv
    ```

    ```shell
    source .venv/bin/activate
    ```
    
    **windows**
    ```shell
    source .\.venv\Scripts\activate
    ```

    ```shell
    pip install uv
    ```

3.  **Install dependencies:**

    ```shell
    uv sync --all-extras
    ```
4.  **Run unit tests:**

    ```shell
    uv run pytest ./tests/unittests
    ```
5.  **Run pyink to format codebase:**

    ```shell
    uv run pyink  --config pyproject.toml ./src
    ```

6. **Build the package**
    ```shell
    uv build
    ```

7. **Local Testing**
    Have a simple testing folder setup as mentioned in the [quickstart](https://google.github.io/adk-docs/get-started/quickstart/)
    then install the local package with changes after building it using the below command to test the changes.

    ```shell
    uv pip install <YOUR_WHL_FILE_PATH>

    [eg]: uv pip install <ADK_PROJECT_PATH>/dist/google_adk-0.4.0-py3-none-any.whl
    ```

### Code reviews

All submissions, including submissions by project members, require review. We
use GitHub pull requests for this purpose. Consult
[GitHub Help](https://help.github.com/articles/about-pull-requests/) for more
information on using pull requests.