Application discovery is an early technical validation step that involves collecting the information about applications in scope of a potential robotics use case. During discovery you need to find out application types (and if they are on applications support matrix for Pega Robotics), how they are launched, how they are used, and check accessibility and functionality of the controls through interrogation. Application discovery is necessary to ensure that robotics use case is viable and it doesn't have any technical constraints... or, if constraints exist, then what kind of workarounds will be necessary to ensure the use case is successful. The rationale for having application discovery as a best practice is that you don't want to find out half-way through coding an automation that a key control is not available or not performing the desired action.