There is no public API yet. It is planned, and this page is where its documentation will live — here is what it will expose, and what to do in the meantime.
The same records the site serves: networks and their site lists, sites and their networks, verification states with their evidence, niches, authority, and the movement log of joins and departures. The data model is deliberately small, and the API will be too — read-only endpoints over exactly what you can already see in a browser.
If you have a concrete integration in mind, email [email protected] — early interest genuinely shapes what gets built first, and for most one-off needs a bulk export covers the gap today. Progress lands on the changelog.