I would guess that they're running multiple instances of Claude Code [0] in the background. You can give it arbitrary tasks up to a complexity ceiling that you have to figure out for yourself. It's a CLI agent, so you can just give it directives in the relevant terminal. Yes, they have access to the filesystem, but only what you give them.
> Those tasks can take hours, or at least long enough where multiple tasks are running in the background?
Maybe not hours, but extended periods of time, yes. Agents are very quick, so they can frequently complete tasks that would have taken me hours in minutes.
> The page says $17 per month. That's unlimited usage?
Each plan has a limited quota; the Pro plan offers you enough to get in and try out Claude Code, but not enough for serious use. The $100 and $200 plans still have quotas, but they're quite generous; people have been able to get orders of magnitude of API-cost-equivalents out of them [0].
> If so, it does seem that AI just replaced me at my job... don't let them know. A significant portion of my projects are writing small business tools.
Perhaps, but for now, you still need to have some degree of vague competence to know what to look out for and what works best. Might I suggest using the tools to get work done faster so that you can relax for the rest of the day? ;)
[0]: https://xcancel.com/HaasOnSaaS/status/1932713637371916341
Those tasks can take hours, or at least long enough where multiple tasks are running in the background? The page says $17 per month. That's unlimited usage?
If so, it does seem that AI just replaced me at my job... don't let them know. A significant portion of my projects are writing small business tools.