Bots can be extremely sophisticated such as (i) generating pseudo posts which look like human generated to interact with humans on a social network, (ii) reposting post, photographs or status of the others, and (iii) adding comments or likes to posts, (iv) building connections with other accounts.
The Analytical Engine.
This isn't a true story, but the residue of historical research mixed with some of the fictional elements for my writing project The Maharajagar.