The General Bikeshare Feed Specification (GBFS) is documented in detail in the open-source project GBFS: https://github.com/MobilityData/gbfs

For the LastenradBayern project the following API's are implemented

1.  station_information: https://www.lastenradbayern.net/GBFSout?request=stations_available
2.  vehicle_status:  https://www.lastenradbayern.net/GBFSout?request=bikes_available