They may act according to various parameters they read in from the system environment. I expect they will be developed to a level of complication where they have something that could reasonably be termed a model of the world. The present approach is closer to perceptual control theory, where the sysadmin has the model and PCT is part of the implementation. 'Cos it's more predictable to the mere human designer.

Capacity for self-improvement is an entirely different thing, and I can't see a sysadmin wanting that - the sysadmin would run any such improvements themselves, one at a time. (Semi-automated code refactoring, for example.) The whole point is to automate processes the sysadmin already understands but doesn't want to do by hand - any sysadmin's job being to automate themselves out of the loop, because there's always more work to do. (Because even in the future, nothing works.)

I would be unsurprised if someone markets a self-improving system for this purpose. For it to go FOOM, it also needs to invent new optimisations, which is presently a bit difficult.

Edit: And even a mere daemon-like automated tool can do stuff a lot of people regard as unFriendly, e.g. high frequency trading algorithms.