Having done something like this a lot, it does not work for me to have a bot. The predictability and lack of social accountability (one should be honest) causes it to fail.
It also lacks a huge benefit:
It turns out that doing something "with" someone, despite a lack of collaboration, has significant social value. Even more so if you do it in the same room or at worst the same video conference.
For this reason I moved from the many tools that exist to do this with strangers to arranging an hour with a friend. This works exceptionally well and has strengthened my friendships despite us living in different cities (I am in a small* town); likely because it keeps us present, real, and approachable in each others minds.
*small by southern English standards; huge by the standards of the northern county I grew up in.