New models, releases, and articles. A score is the average number of questions per round, with a fixed penalty for failed rounds. Lower is better.
Claude Haiku 5.5 (high) joins the leaderboard.
It averaged 20.00 questions per round in edition 1.1, 15th of 21 models, with 5 failed rounds out of 30. Compared with GPT-6 Luna (high) at 21.17, it needed fewer questions on seven of the ten subjects, with clear leads on Garfield and Achilles. Spider web was its weak spot: 30, 38, and 21 questions, against Luna’s 16, 22, and 15.
Gemini 4 Argon (high) matches the lowest average score.
It averaged 13.67 questions per round in edition 1.1, the same as GPT-6 Astra (high): both used 410 questions over 30 rounds and solved every round. Astra ranks first because its 95% confidence interval is narrower. Argon was the best of 20 models on Door handle and second on Albert Schweitzer and Bike pump, but 19th on Moon, which took it 11, 12, and 14 questions.
It averaged 19.63 questions per round in edition 1.1, 13th of 19 models at the time. Some subjects were much harder for it than others: it was 9th best on Albert Schweitzer but 18th on Garfield, which took it 10, 22, and 30 questions. Achilles took 8 questions every time.
Behind Deep20Bench: the hard part wasn’t the game.
Patrick writes about what it took to build Deep20Bench: wrong answers from the answering model, the blind second check, format errors, and the design choices along the way.