{"slug": "capable-yet-parsimonious-extracting-and-characterizing-hidden-chain-of-thought", "title": "Capable yet Parsimonious: Extracting and Characterizing Hidden Chain-of-Thought in Frontier Models", "summary": "A new paper reports that frontier language models can be induced to externalize their hidden chain-of-thought traces by registering a simple custom tool through a standard API feature, allowing researchers to extract and characterize reasoning that closed-source systems normally keep hidden. The work attributes the rapid capability gains of frontier language models to improved reasoning abilities that were previously unverifiable because raw CoT traces in closed-source systems are hidden.", "body_md": "The rapid capability gains of frontier language models are widely attributed to improved reasoning abilities, yet this cannot be verified as raw CoT traces in closed-source systems are hidden. By registering a simple custom tool through a standard API feature, we induce frontier models to externaliz", "url": "https://wpnews.pro/news/capable-yet-parsimonious-extracting-and-characterizing-hidden-chain-of-thought", "canonical_source": "https://aiflash.com/news/125554/", "published_at": "2026-09-24 13:30:00+00:00", "updated_at": "2026-09-24 13:33:34.939107+00:00", "lang": "en", "topics": ["artificial-intelligence", "large-language-models", "ai-research", "ai-safety"], "entities": [], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/capable-yet-parsimonious-extracting-and-characterizing-hidden-chain-of-thought", "markdown": "https://wpnews.pro/news/capable-yet-parsimonious-extracting-and-characterizing-hidden-chain-of-thought.md", "text": "https://wpnews.pro/news/capable-yet-parsimonious-extracting-and-characterizing-hidden-chain-of-thought.txt", "jsonld": "https://wpnews.pro/news/capable-yet-parsimonious-extracting-and-characterizing-hidden-chain-of-thought.jsonld"}}