You should essentially never do syn/ack IRL. If you don't know precisely what the recipient is doing, you do not know what they are doing, it could be important. Always lead with info to help them prioritize things. Ideally in the first ~5 words, because that's all they may see in the notification.
(this is also IMO why phone calls are terrible. they're the equivalent of "hello" over a channel that has no other message, so everything must be assumed to be maximum urgency or you might miss something truly critical)
You should essentially never do syn/ack IRL. If you don't know precisely what the recipient is doing, you do not know what they are doing, it could be important. Always lead with info to help them prioritize things. Ideally in the first ~5 words, because that's all they may see in the notification.
(this is also IMO why phone calls are terrible. they're the equivalent of "hello" over a channel that has no other message, so everything must be assumed to be maximum urgency or you might miss something truly critical)