Agent Harness 2026: Why AI’s Operating System Replaces Model-Centric Thinking

Agent Harness is the critical AI infrastructure wrapping models to manage long-running tasks, acting as an operating system to ensure reliability. It solves the model durability crisis by validating performance over hundreds of tool calls, transforming vague workflows into structured data for training. 2026 AI Evolution: Why the Agent Harness Replaces the Model-Centric Focus We are standing at a definitive turning point in the evolution of Artificial Intelligence. For years, our collective gaze has been fixed almost entirely on the model itself. We obsessed over a single question: “How smart is this model?” We religiously checked leaderboards and pored over …