How to start Agent Script after agent gets logged in USD(Unified Service Desk) or on Button Click i.e. without starting a session

Hi All.

I have a requirement in USD(Unified Service Desk). I want to show an agent script on button click or after the agent gets login. I searched and found that the agent script can be shown only if session starts. Here, I want to show the script without starting any session.

Thanks in advance..