DocFit is a GitHub App for one job: keeping API documentation in step with the code that just merged.

The problem is familiar to anyone who maintains API docs, public or private. A pull request merges, the code is correct, and a docs page is now wrong. Often it isn't the headline change. In our public example, a PR titled "filter refunds by reason" also lowered the maximum page size from 100 to 50, and the docs page never listed the limit at all. Nobody reviewing the code saw the docs page; nobody owning the docs saw the code PR.

What DocFit does on every merge:

1. Decides whether docs could be affected. If not, it leaves a "No docs impact" comment and stops.

2. Reads the whole change: diff, commits, review comments and the linked Jira or GitHub issue.

3. Finds affected pages using the OpenAPI diff, exact names from the code (routes, enums, env vars, CLI flags) and search over your docs, with a reason for each page.

4. Fixes the documentation in your documentation framework's format.

5. Checks it: your docs build and linters, links, OpenAPI lint, and any custom commands.

6. Opens a docs PR for your team and notifies you over Slack. DocFit never merges.

Works with Mintlify, Docusaurus, Redocly/OpenAPI, MkDocs, Nextra, VitePress and plain Markdown, in the same repo or a separate docs repo.

See real output without signing up:

- the code PR: https://github.com/Docfit/example-payments-api/pull/1

- the docs PR DocFit opened: https://github.com/Docfit/example-payments-docs/pull/1

Free for public repos and one private repo. During setup you can dry-run it on your last 5 merges and see what it would have changed.

We're also looking for a few design partners with public/private API docs: Team plan free during early access, in exchange for honest feedback on the docs PRs. Reply here or email [email protected].

I'd love to hear any suggestions or feedback.