Claude Fable 5.2 Launches, Leading Opus 5.5 and GPT-6 Across Benchmarks
Claude Fable 5.2 launched on November 10, and official benchmark comparison tables shared by multiple users (markk, accourtt, MoneyAd3945, etc.) show the new model leading Opus 5.5, GPT-6 Astra, and Gemini 4 Carbon on nearly all of roughly 12-13 evaluations, with major gains over the previous Fable 5.1.
Confirmed
- On the agentic coding benchmark FrontierCode 2.0: Fable 5.2 scores 49.1%, versus 32.4% for Fable 5.1, 45.5% for Opus 5.5, and 42.8% for GPT-6 Astra, ranking first
- FrontierSWE v2 reaches 69.9%
- Robotics scores jump from 27.6% to 64.9%
- minchoi notes Fable 5.2 costs roughly half as much as Opus
- The benchmark table spans comparisons across Fable 5.1, Opus 5.5, GPT-6 Astra, and Gemini 4 Carbon
Why it matters
- FrontierCode 2.0 measures whether a model's code changes would be merged by open-source project maintainers, making it an agentic coding metric close to real-world engineering ability; Fable 5.2 topping it at half the cost is directly relevant to anyone invested in coding automation
- Benchmark data shared by multiple independent accounts corroborate each other, suggesting wide circulation, but all are reposts of the official table, with no deeper independent evaluation yet
2026-11-10 ~ 2026-11-10 · 5 related posts
- Episode 1: Anthropic's Claude Fable 5.2 and Mythos 5.2 Spotted Rolling Out(2026-11-10, 5 posts)
- Episode 2: Anthropic Launches Claude Fable 5.2 and Mythos 5.2(2026-11-10, 41 posts)
- Episode 3: Shumer Reviews Fable 5.2: Smartest Model Ever, But Heavy Guardrails(2026-11-10, 3 posts)
- Episode 4: Claude Fable 5.2 Launches, Leading Opus 5.5 and GPT-6 Across Benchmarks(2026-11-10, 5 posts)
- Episode 5: Fable 5.2 Wins Praise for Open-Ended Tasks(2026-11-10, 2 posts)
Primary sources
- Fable 5.2 benchmarks leak: 49.1% FrontierCode, robotics jumps to 64.9%, 89.3% computer use — ChrisGPT · 2026-11-10
- Claude Fable 5.2 lands: beats Opus 5.5 and GPT-6 across agent benchmarks — accourtt · 2026-11-10
- [source] Claude Fable 5.2 benchmark dump: sweeps 12 evals, robotics jumps to 64.9% — mark_k · 2026-11-10
- Fable 5.2 released: sweeps agentic coding, cybersecurity and robotics benchmarks — Money_Ad_3945 · 2026-11-10
- Fable 5.2 tops FrontierCode 2.0 at 49.1%, matching Opus Max at half the cost — minchoi · 2026-11-10