Claude Opus 5 solved a screenshot-only Rubik’s Cube benchmark in 44 minutes
Various-Affect4841 · reddit · 2026-07-26
- A new benchmark called TWIST tests models on Rubik’s cubes where they can only perceive the state through screenshots.
- Claude Opus 5 solved a 20-move scramble on the 3×3 cube.
- Reported stats: 83 moves (vs. 19 optimal by kociemba), 44 minutes wall clock, 2617 seconds of thinking, 25 seconds of cube movement, 73 screenshots, 240k tokens, max effort.
- The author notes that some of the planning may be aided by retrieval because cube algorithms are common in training data.
- A mirror cube variant is planned as a control to remove color-based cues.
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