PR Auto Explanation

PR Auto is a GitHub tool that writes pull request descriptions for you automatically. When someone opens a new pull request in your repository, this action reads the code changes and uses an AI model to generate a clear, comprehensive description of what changed and why. Instead of developers manually typing out PR summaries, the tool does it in seconds—saving time and ensuring consistency across your team's contributions.

The way it works is straightforward. When a pull request is created, PR Auto connects to an AI language model (by default OpenAI's GPT-4o-mini, but you can swap in other providers like Fireworks or Together.ai if you prefer). It analyzes the pull request metadata—things like which files changed, the branch names, and commit information—then feeds this to the AI model along with instructions on what kind of description to generate. The AI then writes a summary and posts it automatically as the PR description in GitHub.

Setting it up requires just three things: an API key from your chosen AI provider stored in your repository secrets, permission for GitHub Actions to write to your PRs, and a simple configuration file that tells GitHub when to run this action. The README provides a minimal example that takes just a few minutes to add to your repository. You can also customize the instructions given to the AI by providing your own system or user prompts, letting you shape the style and tone of generated descriptions.

Teams use this when they want to streamline their code review process, reduce the overhead of documentation, or maintain consistent PR quality across many developers. It's particularly useful for teams working across timezones or those managing high-volume repositories where manual PR descriptions become a bottleneck. The action includes built-in safety measures so it only reads pull request metadata and doesn't execute any code, making it safe to use even with contributions from external forks.