News•Feb 17, 2026
Harness Engineering
OpenAI’s team spent five months building a "harness" that lets AI agents maintain a production‑grade codebase exceeding one million lines, without a single line of manually typed code. The harness blends three pillars—continuous context engineering, deterministic architectural constraints, and periodic garbage‑collection agents—to keep the system reliable and maintainable. When an agent falters, the failure becomes a signal, prompting Codex to generate missing guardrails or documentation and feed them back into the repository. The approach emphasizes iterative feedback loops over pure model improvements.
