The API should provide an Option to set the bot Flag on registration.
This flag should only be changeable by an administrator over the Admin interface after registration.

Clients shouldn't implement this

Difference to normal Users:

• don't get Posts assigned (and can't vote on them)
• doesn't get most of the emails
• can't message users unless they messaged the bot first
• can subscribe to slash commands
• more rate limited (excluding responses to slash commands)
• can't log into clients
• can have an already registered email address

A bot can be marked as trusted by an Administrator. This will have the following effect:

• can subscribe keywords
• can subscribe users
• can message even if not messaged before
• no rate limiting