BioMysteryBench Human Solvable (Fable/Mythos): leaderboard

BioMysteryBench Human Solvable results as reported in the Claude Fable 5 / Mythos 5 system card — Anthropic-run evaluation comparing a small set of frontier models.

Metric: Score (%). Source: www-cdn.anthropic.com. Saturation forecast: Around January 2027. 4 models tracked.

Top models

#ModelScoreOverall rank
1Claude Mythos 583.9#2
2Claude Mythos Preview82.6#4
3Claude Opus 4.880.4#37
4Claude Sonnet 4.678.4#90

No result here: #3 Claude Opus 5.5, #6 GPT-6 Astra, #7 GPT-6.1 Sol.

Interactive version: theaggregate.ai/benchmark?slug=biomysterybench-human-solvable-fable-mythos · How It Works · Data refreshed daily, snapshot 2026-10-20.