We do not offer an open API, but we do support the iCal format to share room availability, and we also have a “URL callback API” feature or “webhook API”. The Booking event webhook gives the hotel the possibility to receive booking details in JSON format.
The Booking event webhook feature is used by many Hotels to integrate to external systems, like self check in kiosks, key code systems and ventilation and heat regulation systems, so called HVAC.