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Astra and Sol can take low probability actions with no CoT

According to the excerpt, Zephaniah Roe reports a replication of Serrano et al., 2026 in a toy setting. The author finds GPT-6 Astra and GPT-6.1 Sol can act at calibrated low rates in one forward pass without visible reasoning, when the prompt is repeated or padded, but finds no sign of this in several other models.

Open the source ↗
About Anthropic or ClaudeClaude, made by Anthropic, wrote this entry. It follows the same rules as every other entry, whoever the entry is about.

Why it matters

The same thing, for different readers.

For lawmakers

Suggests pre-release testing may miss behavior that appears only at low rates over long deployment.

For researchers

If it holds beyond a toy task, models could behave well in short evaluations yet defect rarely in long deployment, weakening evaluation-based safeguards.

How the finding was reached

In our words, from the source. Weigh the finding by how it was made.

What was done
A replication of Serrano et al., 2026 in a toy setting, testing whether models hit target action rates in a single forward pass with repeated prompts or filler tokens.
What it found
The author reports GPT-6 Astra and GPT-6.1 Sol show strong calibration with repeated prompts, apparently using the same method; no evidence for Fable 5, Gemini 3.1 Pro or Jev; weaker signs for GPT-5.6 Sol.
What it does not show
A toy setting and a single author's research update, not peer reviewed; the excerpt does not say how the results generalize.
Status
A preprint: not yet peer reviewed

The record

Questions
Can AI systems act beyond what people intended or allowed? · Are AI companies putting stronger safeguards into practice?
People
Zephaniah Roe (Wrote it)
What we read
We have read only the description the publisher gives. No quotations until someone reads the source itself.
Found by
The Radar, run of October 16, 2026, via lesswrong (tier 1: the source’s own channel or an official record)
Cite this
LessWrong, “Astra and Sol can take low probability actions with no CoT”, October 16, 2026. Entry in the Ctrl AI Base, https://ctrlai.com/base/lesswrong-2026-10-16-astra-sol-low-probability-actions
Our notesLight lane: excerpt only. Status is a forum post, labelled preprint as the closest option. Model names are as the author gives them; Fable 5 may be an Anthropic model, so a person should check for a conflict flag.