I think he's referring to https://news.ycombinator.com/item?id=37125118 https://news.ycombinator.com/item?id=37125118 Controlling token outputs to match a rege

I think he's referring to https://news.ycombinator.com/item?id=37125118 https://news.ycombinator.com/item?id=37125118 Controlling token outputs to match a regex generates valid JSON 100% of the time!