Chain-of-thought prompting

Asking a model to work through intermediate reasoning steps before giving its final answer, which helps on multi-step problems.

Last updated: November 9, 2026 · Markdown version

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How to apply it in prompts

Use this concept to reduce ambiguity and improve consistency. If you need strict formatting, combine it with a JSON guide and a per-model template.

Related terms:Prompt chaining Zero-shot prompting

Strict JSON Models Packs

What it means

Definition: instead of jumping to an answer, the model writes out the steps — restating the problem, working through the logic, then concluding. The technique is usually triggered with a phrase such as 'think step by step' or a structure with a reasoning block and an answer block.
Why it matters: on multi-step math, logic and planning, errors compound when the model answers in one hop; showing the steps makes them less likely and lets you see where the reasoning broke.
How to apply it: ask for the reasoning first and the final answer last, keep the two separated (for example in tags) so a program can read only the answer, and ask it to check its work before concluding.
Common mistake: adding it by reflex. Models that reason internally often do not need an explicit 'think step by step', and extra process instructions can get in their way — see the guide on reasoning models and check the provider's advice for the model you use.

Copy-paste example

Problem: [describe the problem]

First, inside <reasoning> tags: restate what is asked, list what is known and what is missing, then work through the logic in small steps.
Then, inside <answer> tags: give only the final answer in one or two sentences.
Before the answer, check your reasoning for a mistake.

Opens the analyzer with the prompt prefilled.

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FAQ

Does chain-of-thought always improve accuracy?

No. It helps most on multi-step problems. For simple lookups or classification it adds length and cost without much benefit.

Should I show the reasoning to end users?

Usually not. Keep reasoning and answer in separate blocks and display only the answer; use the reasoning for debugging.