Documentation

user management https://manual.calibre-ebook.com/server.html#managing-user-accounts-from-the-command-line-only

User Management

Add/Modify Users

# create/edit users
# (execute when calibre-server started w/o --enable-auth)
sudo -u calibre calibre-server --manage-users

Enable User Auth

# /usr/local/etc/rc.d/calibre

# add '--enable-auth' to your servicefile's command args
command_args="${command_args} ... --enable-auth"