8 Sept 2026
GPT-6 Astra Is Here: Same Price as Fable 5.1 — and the Harness Number That Decides Whether to Switch
(01)GPT-6 Astra costs exactly the same as Fable 5.1 on the API. But 62.7% vs. 99.9% on ARC-AGI-3 shows that the headline number belongs to the harness. With a reading strategy and decision matrix for agent builders.
OpenAI