::this is a repost of an earlier reply::
This is a common request when it comes to alarm systems and door/window contact sensors. There are a multitude of recessed z-wave sensors on the market that can connect to the Ring alarm system. For the unaware, a recessed door/window sensor is hidden when the door/window is closed. However, Ring only allows these third party sensors to chime the base station when the door/window is opened. It does not activate the alarm nor does it allow a notification to be sent.
It’s 2020. There is no need to place a brick sensor on the outside of your door or window. Many potential customers look elsewhere when they discover the only sensor option is obtrusive and aesthetically unpleasant. Ring must allow third party sensors full access or produce one of their own. It’s a lost sale over a $20 sensor.