What the Diff is an AI code review assistant that explains every pull request in plain language and comments on changes automatically.
What the Diff focuses on communication. It generates readable summaries of what a pull request actually changes — written for reviewers, product managers and anyone following the project — and posts AI comments on the code itself to flag issues or suggest improvements. The summaries can be sent to Slack or email so stakeholders stay informed without reading diffs.
The tool is quick to install on GitHub, respects a per-repository configuration, and lets teams tune how chatty it is. It also offers a changelog generation feature that turns merged pull requests into release notes your users can understand.
The tool’s summaries are written for audiences beyond engineering: product managers, designers and executives can follow what shipped without reading code. For teams that maintain release notes, the changelog feature turns merged pull requests into user-facing announcements with minimal editing. Configuration is lightweight — install the GitHub app, choose repositories, and tune the tone and verbosity of the generated comments and summaries to match your team’s culture.
What the Diff has a free tier for open-source and small projects, with paid plans based on the number of active contributors and private repositories.
Teams where reviewers, PMs and other stakeholders need to understand code changes quickly without reading raw diffs.
Yes for open source and small teams; paid plans cover private repositories and higher activity volumes.
It is primarily a GitHub app with notification integrations rather than a public API product.
It competes on clarity of explanation and stakeholder communication more than on deep static analysis.
What the Diff is a GitHub app today, with summaries, comments and changelog features delivered through GitHub and notifications to Slack and email.
Teams use What the Diff to keep non-developers informed: automatic pull request summaries for PMs and stakeholders, AI review comments for authors, Slack notifications for the wider team and generated changelogs for releases. It is particularly valuable in organizations where many roles need to follow engineering output without reading code.