Hello, I recently made a network device presence sensor driver to fit my needs. I was using an Hubitat-iPhone-Presence-Sensor with some code changes but recently I had more problems with my RPi and that driver was not enough to check my RPi presence.
The main difference between my driver and the previous is that you can define a protocol (http/https), you can enter a search phrase that your device should return and when the protocol is set to https it can ignore the certificate issue (I think it will fit most of your needs).
So in my case I have an httpd docker image on my RPi which returns a phrase that my driver checks for. Why is that for? Sometimes the RPi can hang and return a blank page which somehow gets the 200 status. So the only way to check if it's alive is to check if it's returning that it should.