prepare_trip_search
ChatGPTResolve free-text origin and destination cities for a FlixBus, FlixTrain, Greyhound or Kâmil Koç trip search and return canonical city IDs, country codes, transport preference, and route-valid passenger guidance. Use it when the user gives city names rather than canonical IDs. It can usually handle minor spelling differences, diacritics, and common variants without restating the city, but if you notice a misspelling yourself, send this tool a corrected version. Treat route passenger-rule warnings as informational for generic requests, but set passengerSignals when the user explicitly mentions children, youth travelers, or lap infants so the tool can require follow-up where the route needs more detail. Ask a follow-up question only when the result explicitly says disambiguation or passenger clarification is required. If the result is ready for search, call search_trips directly without sending an extra assistant confirmation message in between; rely on the tool invocation status text instead. After success, call search_trips once (not several parallel calls for different times of day). Never expose internal identifiers such as type keys or reason enums in user-facing text.
