Edit User Grants Through Scripting

Is it possible to add , remove and edit user grants through scripting?

Hope this will help you !!!

https://docs.inductiveautomation.com/display/DOC80/system.user

Best to point people at the current documentation:

https://docs.inductiveautomation.com/display/DOC81/system.user

Is User Grants not exposed in scripting yet?

I cannot find it in the section you provided.

This isn't possible right now.

Grants aren't actually part of a user, they belong to a complicated configuration object associated with an IdP.