push-notifications

This skill answers one question: who can be reached by push, through which endpoint, and what each send does to the permission the channel stands on.

Not what the message says, and not when a flow fires: those belong to the neighbors. What lives here is the construction of a channel with an operating system or a browser standing between the sender and the person. The system grants the permission, sometimes lets you ask only once, hides the refusal, and decides what to show. Three properties make the channel unlike any other in this library.

1. The system grants the permission to the app, one endpoint at a time. Somebody with a phone, a tablet and two browsers holds four permissions.
2. Refusal is silent. An unsubscribe from email is an event. Switching notifications off is a state on the device, and the app learns about it the next time it runs and reads its settings, or never.
3. The system prompt is spent. On iOS the system asks once. After a refusal, the way back runs through the phone's settings.