Chain-of-Thought Prompting

Chain-of-thought can be triggered in two ways: few-shot CoT includes example problems with their step-by-step solutions, teaching the model to mimic that format. Zero-shot CoT uses a simple suffix like "Let's think step by step" to activate the same behavior without examples.

• • Few-shot CoT: provide worked examples showing reasoning steps in the prompt.
• • Zero-shot CoT: append "Let's think step by step" to elicit reasoning without examples.
• • Self-consistency: sample multiple reasoning chains and take the majority answer for higher accuracy.

Chain-of-thought is most valuable for tasks requiring multi-step logic: math problems, strategic planning, code debugging, and legal or financial analysis. For simple retrieval or classification tasks, CoT adds latency and cost with minimal benefit.