Not exactly sure what you want to achieve. Do you have so many applications in the environment? Still, every application needs to be somehow set-up (user action naming, user tagging, XHR setup, etc...) to produce meaningful monitoring results.
The best option about detecting "URLs" to be potential new applications or unknown endpoints of current application would be to capture 100% of the default RUM application and manage them continuously. Either transfer to existing applications or to a disabled one.