In plain language
Instead of answering immediately, the model plans, checks its work, and then gives the final answer.
Example
A reasoning model compares three vendor contracts clause by clause before recommending which one fits a policy.
Related terms
Large Language Model (LLM) · AI Agent · Evals · Token (AI)
Common misconception
More reasoning is not always better; it adds cost and time, and simple extraction or classification rarely needs it.
Implementation guidance
Use reasoning for multi-step analysis and planning, keep fast models for simple steps, set budgets for thinking time, and evaluate whether it improves results.