"the modern AI age" doesn't really change the realities here. If you're an employee and you're at work (contracted/customary working hours, using employer's eq

"the modern AI age" doesn't really change the realities here. If you're an employee and you're at work (contracted/customary working hours, using employer's equipment/facilities) then its reasonable for your employer to want you to work for them. There will likely be a tacit understanding that occasional brief web browsing or life admin tasks are acceptable, for example. But on the whole they'll expect you to be doing employee tasks.