The Assistant user group functionality is to be able to create visitors on behalf of other users.
Let's start with the Setup:
To access the user rights for an Assistant, go to settings and under General Settings click on User rights. Here is where you will see all of the User Groups and have the ability to configure which features they can have access to.
Below is our recommendation of what user rights the Assistant user group should have. (🔎click the image to zoom in and download a PDF version)