## ChangeLog

- **2026-03-10:** Added specs for site and shallow links.
- **2025-11-07:** Clarified the relationship between price and availability. Added more samples.
- **2025-07-22:** Relocated API errors, improved format, lint, and highlighting.
- **2025-07-15:** Added a new [Glossary](https://developers.google.com/travel/transport/guides/partner-integration/glossary) and improved documentation for integration types, partner configuration, and how to report currencies and taxes.
- **2025-07-01:** Added [Logos](https://developers.google.com/travel/transport/guides/partner-integration/logos) information and organized the [Ticketing Links](https://developers.google.com/travel/transport/guides/partner-integration/ticketing-links), and updated the [Price Quality](https://developers.google.com/travel/transport/guides/partner-integration/price-quality-testing) page with information to the crawler ips.
- **2023-07-24:** Added the [Participation requirements](https://developers.google.com/travel/transport/guides/partner-integration/participation-requirements) page.
- **2023-07-04:** Added new page [Price Quality](https://developers.google.com/travel/transport/guides/partner-integration/price-quality-testing) to describe the traffic from Google Transport price accuracy crawlers.
- **2023-05-22:** Added new page [`GetBulkTripOptions` method](https://developers.google.com/travel/transport/reference/partner-server/get-bulk-trip-options) for Bulk API trip options.
- **2023-05-15:** Added JSON sample error case to [GetTripOptions](https://developers.google.com/travel/transport/reference/partner-server/get-trip-options) documentation.
- **2023-03-24:** Added details to the specification for HTTP error codes and how they relate to specific values of `TripOptionsErrorType`.
- **2023-03-03:** Added new error type TRIP_OPTION_CACHE_STALE, INTERNAL_ERROR and SUBOPTIMAL_ITINERARY to [`GetTripOptions` method](https://developers.google.com/travel/transport/reference/partner-server/get-trip-options).
- **2023-01-24:** Added new field `booking_token` to the [Stop-only
  Integration](https://developers.google.com/travel/transport/guides/partner-integration/stop-only-integration).
- **2022-12-15:** Added new field `service_date` to the [Stop-only
  Integration](https://developers.google.com/travel/transport/guides/partner-integration/stop-only-integration) for greater consistency with GTFS ticketing.
- **2022-12-14:** Added new field `arrival_time` to the [Stop-only
  Integration](https://developers.google.com/travel/transport/guides/partner-integration/stop-only-integration) to maintain uniqueness of segment keys.
- **2022-08-23:** Added new page [Stop-only Integration](https://developers.google.com/travel/transport/guides/partner-integration/stop-only-integration) to allow partners to integrate with Travel Transport without providing a full GTFS feed.
- **2022-06-01:** Switched to proto3 from proto2 for improved clarity since proto3 is already used in [canonical JSON
  mapping](https://developers.google.com/travel/transport/guides/partner-integration/partner-server#request_response_format).