It is inspired by Digital Selective Calling, a part of the Global Maritime Distress Safety System.
[1][2] It also builds on existing digital procedures inherited from morse code and radioteletype operation.
The text message doesn't necessarily require the station identification commonly seen in voice, CW or RTTY exchanges, so long as the programmed call sign is valid.
When ready to communicate on the coordinated frequency, KJ6VVJ responds with an acknowledgment to the QSX.
If the operating mode isn't obvious in context of the frequency, the initiating stations QSX should specify what it is.