It is just something you can add if you plan to make the account controlled by a script. I think the plan is to eventually add an option to ignore all bot posts, but AFAIK this doesn't exist yet.
Do you have to do something special to truly make your account a bot? Like give it a function it can do as a bot? (I'm not trying to make this account a bot though)
I honestly don't know enough about the Fediverse APIs, but assuming that they provide similar functionality to Reddit's:
I would say a bot account should be reserved for accounts that largely operate automatically with little human intervention necessary.
Just like on Reddit, I would still like to have a Disclaimer on the bottom of posts/comments of such accounts stating that the action was performed by a bot. Ideally with a way to feedback the dev and a link to a GitHub page.
The main thing is that the account is mostly controlled by a computer program (=bot) making decisions on when, where and what to post or comment, rather than a human. Whether it actually serves a useful function or is just randomly shitposting is up to you, I guess 😅
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