Verify a passport.
Two independent checks: the cryptographic signature (works offline, against our published keys) and the live revocation registry. Scanning a passport’s QR brings you here with both done automatically.
Or check a number.
The last character of every passport number is an ICAO 9303 check digit — typos fail before they reach the registry. Holder identity is never disclosed here; it lives only on the document itself.
Building a door that should recognise passports? The full security model — JWKS, token claims, MRZ, all of it.