Isolate a member by stripping roles temporarily or permanently, with auto-restore.
Jail is the punishment between a mute and a ban: the bot strips all of a member roles and gives them a jail role that hides the server except one channel, while saving the roles it took. When the time ends, their roles come back exactly as they were. A heavy penalty that is still fully reversible.
The common trick is for a jailed member to leave the server and rejoin so the jail role disappears. The system handles it: rejoining re-jails them automatically, so the attempt is pointless.
Jail is not a command alone: the warnings system, the protection systems, AI moderation, and the command builder can all jail, with a duration set in each system own settings.
There is a gap between a mute and a ban: a mute is too weak to deter, and a ban is too harsh to walk back. Jail fills it: the bot strips all of a member roles and saves them, and gives them a jail role hiding the server except one channel. When the time ends, their roles return exactly as they were.
The jail role and channel are created by the bot itself if they do not exist, with their permissions set. So you never have to prepare anything by hand and never leave a gap in a channel you forgot.
Restore roles on release is the key setting: turn it off and the member comes out without their roles, making a temporary penalty permanent in practice. As for the common trick of leaving the server and rejoining so the jail role disappears, the system re-jails them automatically on return.
And jail is not a command alone: the warnings system, the protection systems, AI moderation, and the command builder can all jail, which is why a default duration exists for when the calling system gives none.