OpenAI’s Astra model will use recurrent depth, also called opaque recurrence, a reasoning technique reported on Tuesday. The change matters because the method can move reasoning away from the sequential steps that make chain-of-thought easier to follow.
Buck Shlegeris said, "I am extremely concerned by the reporting that Astra uses opaque recurrence." He also warned, "I don’t know whether Astra is much less CoT monitorable than previous models. But if OpenAI pushes this technique further, they’ll have the option to massively increase the recurrence and totally destroys CoT monitorability."
Buck Shlegeris on Astra
Opaque recurrence lets Astra operate outside the sequential thinking that characterizes most reasoning models. For safety teams, that means fewer readable traces to inspect when a model behaves badly or drifts from expected behavior.
OpenAI chief scientist Jakub Pachocki said, "OpenAI has worked to preserve and utilize chain-of-thought monitoring since our very first reasoning models" and added, "It’s a core goal of our current research program." That puts the company’s stated safety plan on the same page as a technique that could make those traces harder to monitor.
Jakub Pachocki and CoT
Wednesday morning brought a wider signal that the technique is not staying inside OpenAI’s walls. The Information said Anthropic and Google DeepMind were already discussing it, while Ryan Greenblatt warned, "My biggest concern is that a natural progression from here would involve scaling up the opaque reasoning to the point where the model reasons entirely or almost entirely in latent space," and Zvi Mowshowitz wrote that laws might be necessary to prevent a race to the bottom among AI labs.
OpenAI has already announced plans for extensive chain-of-thought monitoring systems, so the real test is whether those safeguards can still read enough of Astra’s reasoning to catch failures before they matter. How much opaque recurrence Astra actually uses, and whether that use materially reduces chain-of-thought monitorability, is still the unanswered part.
