The second and third links are identical. Did you miss something?
Bots are allowed and are subject to the same rules as human accounts.
The rules are the same as for humans. But keep in mind:
- No one is allowed to access the site more often than once per second on average. (Somewhat higher burst accesses are OK.)
- Every post must be on-topic. Any bot response to a topic is almost certainly off-topic. Changetip's behavior of responding to user commands publicly would not be allowed, for example.
- If someone complains about an unsolicited PM you send them, then you're probably going to be banned.
If you find a bot / human just copying posts, report it like mexxer-2 said, and the bot accounts will get banned.