I should also say that there have been both official smart things monitoring features and community built monitoring features in the past, but pretty much everyone has abandoned it and moved on to a more reliable system after a few months.
Here’s a typical discussion thread from the past.
But again, a year later hardly anyone was still using their smartthings – based solution for this use case.
I think @rboy had a smartapp for this in his paywall library: but I don’t know if it works with the current architecture and I don’t know if there any plans to transition it to the new architecture, and I don’t know if he even still offers it.