I spent months watching AI coding agents produce impressive demos that couldn't survive production.

The code looked right. It compiled. It even passed the first test.

Then it hit edge cases. Forgotten constraints. A rule the agent agreed to five minutes ago, now gone — overwritten by the next context window.

The root cause wasn't capability. It was process.

"A raw model is not an agent. It becomes one once a harness gives it state, tool execution, feedback loops, and enforceable constraints."