Power Suite Apps for Jira, check whether the Screen script is filled in?

[喵嘞个咪]

Power Suite Apps for Jira, in this plugin, Configuring a Power Actions Custom Field, in the Screen script, I need to check whether the user's input is filled in, when submitting, check whether it is filled in, if not, make a prompt . I checked the official documentation, but there is no relevant information in this piece, or this kind of operation is not allowed.I hope there is a way to do this verification, any help is greatly appreciated.