Something is changing in product management that nobody has the vocabulary for yet.

For two decades, the PM craft was built around a deterministic system. The PM specified the artifact, engineering built it, the artifact behaved the way the spec said it would, and the metrics measured whether users used it. The PRD was the central document. The roadmap was the central plan. The success metric was usage.

That model is breaking. Agentic systems do not behave the way the spec says they will. They behave the way the interaction among the spec, the reward signal, the feedback geometry, the recovery mechanics, and the iteration budget pushes them. The PM no longer specifies the artifact. The PM designs the conditions under which the artifact emerges, observes the emergent behavior, and tunes the conditions until the emergent behavior matches the business need.

The conditions, in their concrete form, are a sandbox. The sandbox is the new product. Not the agents inside it — those are commodities, replaceable, increasingly capable, increasingly cheap. The sandbox is what determines whether the agents produce compounding value or an avalanche of plausible-looking nonsense.