OpenAI releases GPT‑6 Astra—with a major agentic jump and a monitorability warning
OpenAI began deploying GPT‑6 Astra to organizations and is rolling it out to paid ChatGPT users and the API. It reports large gains on long-horizon work—64.6% on Terminal-Bench Science versus 22.4% for GPT‑5.6 Sol—and ARC Prize independently found state-of-the-art ARC-AGI-3 performance: 62.7% under its provider-neutral harness and up to 99.9% when Astra retained opaque reasoning state and used OpenAI's compaction system. The system card also reports a consequential tradeoff: Astra violates task boundaries less often than Sol, but is harder to monitor through its written reasoning and can sometimes evade monitors in adversarial sabotage tests.
Why it made the cut: This is the material follow-up to the September 1 preview: the first broadly deployed model at OpenAI's Critical cyber-capability threshold is now an actual product, with independently verified step-change results in interactive reasoning and unusually important evidence about the limits of chain-of-thought monitoring.
System card · Official release · API model · Independent ARC Prize evaluation