Global model, verified coverage incrementally
Every ISO 3166-1 country is representable. Subnational rows exist for US states, Canadian provinces (GST/HST/PST/QST), Australian states, and nested examples such as US-CA-San-Francisco. Economic unions such as EU are first-class.
Presence in the registry is not production support. Unknown jurisdictions fail closed. Multiple relevant engines without a unique SUPPORTED result yield jurisdiction_ambiguity. Wallet, chain, token, and IP never select an engine.