Hi Caitlyn
Agent script lets you create custom actions, and assign that custom action to a button. that custom action can include many different steps. Open a url, call a dataction, check if a variable is a certain value and if it is then do something else etc. In there you could call a data action that calls a Genesys API to create an evaluation (not sure if that works for a call in progress) or any other API call to other systems or Genesys, making it very versatile.
https://help.mypurecloud.com/articles/define-custom-script-action/
If you outline exactly what you want the button to do, I'm sure someone here can help with any specifics you are missing.
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Anton Vroon
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