Paper traces limits on chain-of-thought controllability to first tokens after thinking tag
Overview
A paper by researchers Elvis Saravia describes says models' inability to control what they write in their reasoning partly underpins chain-of-thought monitoring.
The authors trace much of that limit to entropy collapse in the first few tokens after the opening thinking tag, where models settle on a few common openings.
According to the report, prefilling a single token, or banning frequent opening tokens and adding in-context examples, raised average compliance by 34 to 41 points across models.
Written by AI from the articles below · updated Nov 2, 10:39 AM ET
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elvis@omarsar0XPaper traces chain-of-thought controllability limits to the first few tokensAIThe paper finds that chain-of-thought monitoring depends partly on models being unable to control what they write in their reasoning. It traces much of that limit to entropy collapse in the first few tokens after the opening thinking tag, where models fall into a few common openings. Prefilling a single token, or banning frequent opening tokens and adding in-context examples, raised average compliance by 34 to 41 points across models.

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