GPT-6 Astra makes major gains in the Artificial Analysis Coding Agent Index

GPT-6 Astra scores 67 on the Artificial Analysis Coding Agent Index, matching Claude Opus 5, Fable 5 and Muse Spark 1.3, while using about one-third the tokens of GPT-5.6 Sol. It ties GPT-5.6 Sol at 61 on the Intelligence Index, reduces output tokens 10%, cuts hallucinations from 92% to 51% with a 4-point accuracy gain, and costs under half the per-task price of Claude Fable 5, though its pricing is 2.5× higher, making it roughly 75% more expensive per task.