AI 10 min read
Harness Engineering: The OS Behind 5 Companies
What 200+ AI Engineers Named the Thing I Already Run
In early 2026, engineers from OpenAI, Anthropic, IBM, and Google DeepMind independently described the same discipline: harness engineering — everything around the model that makes an agent reliable. I run five AI-native companies on it with zero hired employees. This is the teardown: the 5 artifacts, the principles, and why the harness is built to be deleted.
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