The Alert mechanism is highly versatile and provides contextual information to transit users for events that happen in the network. In particular, it informs users of the following:
- Cancellation of routes, network, stops, and trips using
NO_SERVICEin effect field
- Transit announcements and notices with no effect on routing. For example:
- On-the-fly addition or reduction of trips
- Stop closures or movements
For more information, reference the GTFS documentation.
Recommended guidelines for providing an Alert: