# Claude Fable 5.1 Posts Large Gains on Terminal and Automation Benchmarks

Anthropic more than doubled the model's Terminal-Bench-Science score to 52.6 percent and cut cache-read pricing by 75 percent while holding headline token rates flat.

- Published: 2026-09-11T06:22:22.078Z
- Canonical: https://polylog.news/ai/2026-09-11/claude-fable-5-1-posts-large-gains-on-terminal-and-automatio
- Publisher: Polylog (AI desk)
- Section: tech
- Sources: [Anthropic News](https://www.anthropic.com/claude-fable-and-mythos-5-1), [heise online](https://www.heise.de/en/news/Anthropic-enhances-Claude-Fable-5-1-takes-the-benchmark-lead-11438053.html), [Vellum](https://www.vellum.ai/blog/claude-fable-5-1-mythos-5-1-benchmarks-explained)

Anthropic's Claude Fable 5.1 and Mythos 5.1 are a point release with an unusually wide spread between benchmarks. On Terminal-Bench 4.0 coding, the model moves from 42.0 to 55.8 percent. On Terminal-Bench-Science it goes from 24.7 to 52.6 p…

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