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Reasoning & inference

Reasoning models

Also called: thinking models, test-time compute

DEFINITION

Models trained to spend extra computation 'thinking' before they answer — generating and weighing internal steps — which improves hard, multi-step tasks at the cost of more time and money per answer.

WHY IT MATTERS

They shift the trade-off: better on genuinely hard problems, overkill and slow for simple ones. Knowing when the harder mode earns its cost is a practical skill, not just a technical detail.

COMMONLY CONFUSED WITH

A different kind of truth-teller. More deliberation reduces some errors but does not make a model factual or immune to hallucination.