AI pull request description generator
Turn a branch diff or commit list into a PR description with summary, risks and a test plan.
Your key stays in your browser.It goes straight to the provider, never to our servers, and we neither log nor keep it. Use a dedicated key with a spending cap, and delete it in the provider's dashboard when you are done.
Input
Result
The result will appear here.Reviewers read the description before the diff, and a good one — what changed, why, what could break, how to test it — gets a PR merged faster. Paste git diff main...HEAD, the output of git log, or both, and get a title plus Summary, Changes, Why, Impact and risks, and How to test sections. The prompt adapts the write_pull-request pattern from danielmiessler/Fabric, and adds a rule it lacked: never invent ticket numbers, benchmarks or motives the diff does not show; say it is unclear instead.
How it works
- The title follows Conventional Commits when your commit messages already do, and otherwise is a plain description of the change.
- Lock files are removed from the diff before sending and listed by name, which keeps large dependency bumps inside the model's context window.
- Migrations, new environment variables and breaking changes get their own place under Impact and risks, where reviewers look for them.
Where your data goes
With your own key, what you type and the key go from your browser straight to the provider you choose; neither passes through Hysen Labs. In hosted mode, your text goes through our server to our provider (DeepSeek) and is billed in credits; we keep the token counts and cost of each run for billing, never the text itself or the answer. How the provider handles the text is governed by its own privacy policy.
This tool handles keys and credentials, so nothing about a run is saved, not even to your own history.
About your API key
We do not collect, store or leak your key: it lives only in this page's memory (unless you tick “remember in this tab”) and is gone when you close it. Still, treat any key you have pasted into a web page with care — create a dedicated key with a spending cap for use here, and delete or rotate it in your provider's dashboard when you are done.
What it costs
This tool is free, with no sign-in and no points.
Common questions
- Which command gives the best input?
- git log --oneline main..HEAD followed by git diff main...HEAD. The commit messages carry the intent, and the three-dot diff shows exactly what the branch changes relative to where it forked from main.
- My diff is huge. Will it work?
- Up to the context window of the model you chose. For very large branches paste the commit list and the diff of the most important files only; the description will be better than one written from a truncated diff.
- Does the diff pass through your server?
- No. It is sent from your browser to the provider you choose, authenticated with your own key. Branch diffs are internal code, so prefer a provider your organisation approves and a restricted key you can revoke once the description is written.
The open-source behind it
This tool's prompt is adapted from danielmiessler/Fabric (MIT) and runs on the model you choose. To use the same capability from the command line or inside your own program, start with that project.
danielmiessler/FabricAlso known as
- pull request description generator
- ai pr description
- generate pr summary from diff
- github pr template ai
- merge request description