From our awesome dev lead for agent scripts comes a workaround:
Scripts do not support arrays yet and so we treat the value sent as a single string and so you cannot do more than one number per action. If you want to do this in one button click just make a custom action that does "add to DNC" as many times as you need with all the numbers. In that way you make one button click and the custom action will fire and do all the api calls you need to do.------------------------------
Chad McCormick
Genesys - Employees
Sr PM
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