GPT-5.5 Tops MineBench Spatial Reasoning Benchmark — But Grok 4.20 and Kimi K2.5/K2.6 Cluster at Top

r/OpenAI·medium signal

GPT-5.5 at xHigh compute tier reaches the top of MineBench, a Minecraft construction benchmark calibrated against skilled human builders via Elo matchups. However, the leaderboard shows Grok 4.20 Beta, Kimi K2.5 Thinking, and Kimi K2.6 all clustered at the top of VoxelBench. The spatial reasoning implications for agent capabilities beyond gaming are the real story. 67↑ on r/OpenAI.