In the current version, permissions are set for user groups that have the right to use the bot.
I suggest adding another permission choice for a group (or groups) of users who don't have access rights, but to whom the bot responds by giving an announcement.
The add-on's settings could have a text field where the administrator could write a notice. Of course, it would be good to consider the language choices. Perhaps it would be easier to use phrases according to the languages, that would also be a perfectly functional solution.
The message would say that, unfortunately, you do not have sufficient access rights to use the bot. However, you can get them by getting a user upgrade and you can do that here <link>.
The bot would not react in any way to user groups that were not selected to receive a notification.
I suggest adding another permission choice for a group (or groups) of users who don't have access rights, but to whom the bot responds by giving an announcement.
The add-on's settings could have a text field where the administrator could write a notice. Of course, it would be good to consider the language choices. Perhaps it would be easier to use phrases according to the languages, that would also be a perfectly functional solution.
The message would say that, unfortunately, you do not have sufficient access rights to use the bot. However, you can get them by getting a user upgrade and you can do that here <link>.
The bot would not react in any way to user groups that were not selected to receive a notification.