aam_show_toolbar
FYI!
It is the custom AAM capability you create if it does not exist. Upon creation, all users and roles that do not have this capability explicitly assigned, will not be to see the admin toolbar on the frontend.
The top admin toolbar, by default, is shown on the frontend after a user authenticates. It is not always needed, especially when the website administrator does not want other users to have access to the backend.
WordPress core already offers the ability to hide the top toolbar for any individual user. However, this process can be time-consuming because a webmaster has to go to each user's profile and deactivate the toolbar.
As an option, you can create a custom aam_show_toolbar capability and assign it only to roles or users that the toolbar can be shown.