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Sonnet 5 vs Opus 4.8: reasoning-effort cost-quality report

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@morganlinton morganlinton released this 01 Jul 13:20
report-2026-07
ebb0d81

VulcanBench v1 reasoning-effort sweep (936 runs, deterministic test grading). Sonnet 5 owns the entire cost-quality Pareto frontier and reaches 100% pass@1 at high effort; all Opus 4.8 configurations are dominated. 4-page technical report (PDF).

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