Check passport and visa requirements and know when to escalate to a human

Steps

1. For programmatic visa and passport requirement lookups, use a Timatic-class data source — IATA Timatic is the authoritative database used by airlines, accessible via reseller APIs (e.g. Amadeus Travel Intelligence, VisaHQ API, Sherpa) rather than directly.
2. Query with: passenger nationality (ISO 3166-1 alpha-2), destination country (ISO 3166-1 alpha-2), transit countries if applicable, and document type (ordinary passport, diplomatic, etc.).
3. Parse the response for: visa_required (boolean), visa_on_arrival_available, entry_validity (single/multiple), minimum passport validity required (often 6 months beyond stay), and any health or vaccination requirements.
4. Flag cases that require human review: stateless persons, refugee travel documents, dual nationals, passengers with prior deportation or refusals, and any case where the API returns 'contact embassy' or 'verify with airline'.
5. Always surface a disclaimer that requirements change frequently and the passenger should verify with the official embassy or consulate — Timatic data is usually current but not legally binding.
6. Never make an autonomous booking decision based solely on a programmatic visa check for a route flagged as high-risk or ambiguous; require explicit human confirmation.