Reasoning Model
Also called: thinking model
A model trained to spend extra compute working through a problem before answering.
Reasoning models generate intermediate steps — a private scratchpad — before producing the final response, and are trained to do this well rather than just prompted into it. They trade latency and cost for accuracy on maths, code, and multi-step analysis. On simple tasks they are slower and pricier with no benefit.
In practice: Fifteen seconds of hidden work before a correct answer, versus one second and a wrong one.