How to use deterministic tooling to hard-enforce code quality
In February 2026, OpenAI published an article about building a complete product without writing a single line of code by hand. An agent did all the work. They used the term harness engineering to describe the discipline around it.
TL;DR: humans steer, agents execute. The team did not write code anymore. Their job was to build the environment around the agent so it could work reliably.
The article groups this work into roughly four sections:
Context — the repository as the single source of truth
