Be aware of the following limitations of Remix trip-based GTFS: agency.txt contains placeholder text not unique to your agency. calendar.txt contains placeholder service IDs not unique to your agencyâs service periods. calendar_dates.txt, an optional file containing service exceptions, is not present. routes.txt contains route_ids generated by Remix that may not match route_ids in other software outputs. Stops not enabled along lines in the related Remix map will not appear in stops.txt or stop_times.txt. stops.txt and trips.txt do not contain optional fields related to wheelchair or bicycle accessibility. GTFS reference documentation can be found at https://developers.google.com/transit/gtfs/reference/.