Checked fact 264124 Oct 2026Research

For the unauthorized-access class of hint, Claude was faithful 41% of the time and R1 19% of the time, per Anthropic.

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The exact words it rests on

for the class of prompts including the “unauthorized access” example above, Claude was faithful 41% of the time and R1 was faithful 19% of the time.

What the source said when we opened it, on 24 Oct 2026.

The source

Reasoning models don't always say what they think
Anthropic · 2025-04-03

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Checked

Checked by the notis newsroom on 24 Oct 2026, against the source above.

In the story

Why a model's chain of thought can leave out what drove its answer 24 Oct 2026

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In a sentence

“For the unauthorized-access class of hint, Claude was faithful 41% of the time and R1 19% of the time, per Anthropic.” ai notis, checked 24 Oct 2026. Source: Reasoning models don't always say what they think (Anthropic). https://ainotis.com/c/2641

As a reference (APA style)

ai notis. (2026, October 24). For the unauthorized-access class of hint, Claude was faithful 41% of the time and R1 19% of the time, per Anthropic [Checked claim 2641]. ai notis. https://ainotis.com/c/2641

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