The author shared this prompt in their post.
build an interactive website about imaginary planets
GPT-6 SOL VS OPUS 5.5 Same prompt : build an interactive website about imaginary planets. Both models on High. GPT-6 Sol → 10 minutes → 3 planets → 1% usage on the 200 plan. Claude Opus 5.5 → 26 minutes → a full explorable solar system with more detail → 16%