Anthropic's Fable 5.1 tops coding benchmark, reaching Pareto frontier
PawelHuryn · x · 2026-09-02
Anthropic's Fable 5.1 achieved top results on the Bug Hunt Bench, marking the first Anthropic model at the Pareto frontier.
Results:
- Fable 5.1 (max): 43/105 bugs fixed
- GPT-5.6 Sol (max): 42/105 bugs fixed
- Grok 4.6 (xhigh): 27/105 bugs fixed
Performance:
- 2.24x faster than GPT-5.6 Sol (max)
- 26% cheaper than Fable 5 (max)
Comments noted that while Fable 5 felt good to use, it wasn't previously the best coder, making this result unexpected.
Related event: Anthropic's Fable 5.1 Tops Bug Hunt Bench, Beating GPT-5.6(4 posts)→
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