For ESTA status checks, use the CBP ESTA API (available to authorized travel service providers) or direct users to the official CBP ESTA portal; submit the application or status-check request with the traveler's passport number, nationality, and date of birth.
Parse the ESTA response status field: 'Authorization Approved', 'Authorization Pending', or 'Travel Not Authorized'; map these to traveler-facing plain language descriptions.
For general visa checks, integrate with a visa requirements database API (e.g., Sherpa°, iVisa partner API) using origin passport country and destination country to retrieve current visa requirements and processing times.
Surface the visa requirement type (visa-on-arrival, e-visa, embassy visa, visa-free) and estimated processing time relative to the departure date; flag if departure is within a risky window.
Monitor ESTA records that are approaching 2-year expiry or the 90-day stay limit; send proactive alerts to travelers who need to renew before their trip.
Store all visa status responses with a timestamp and refresh them periodically since requirements change; never serve cached data older than 24 hours for pre-trip checks.
Known gotchas
ESTA authorization is valid for 2 years or until the passport expires, whichever comes first — always check passport expiry against the ESTA expiry, not just the travel date.
Visa requirements change frequently due to political agreements; a cached 'visa-free' result from weeks ago may be incorrect — always re-verify close to booking and departure.
ESTA approval does not guarantee admission to the US — CBP officers have final authority at the port of entry; communicate this clearly so travelers understand the difference.
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp