Your test suite is the only thing that makes AI agents useful

A company called Reco converted JSONata from JavaScript to Go in 7 hours using AI. Seven. Hours. Not seven sprints. Not seven engineers over seven weeks. Seven hours. And the internet immediately argued about the wrong thing. Everyone wanted to talk about which model they used, which agent framework, which prompt magic made it happen. But the skeptics nailed the real story: this only worked because JSONata already had a rock-solid test suite. The AI didn't understand the code. It executed agains