Vimeo add-on adds new triggers to lets your users to complete automations by watching a Vimeo video.
You can configure any trigger of your choice to being completed by watching a video as explained here.
Is important to know that only videos embedded through the [automatorwp_vimeo] shortcode will be able to complete the trigger.
Also, you can check the automations samples page where you can see some samples of the possibilities of this add-on.