Artificial Analysis Coding Agent Index: GPT-6 Astra scored 67, roughly equal to Claude Opus 5, Fable 5, and Muse Spark 1.3, but trailing leader Fable 5.1's 70 (Artificial Analysis)
Fable 5.1 in Claude Code leads the Index with a score of 70. … Various effort levels of the model occupy the Pareto frontier of token efficiency.
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