Zero-Shot Chain-of-Thought

Problem

Few-shot chain-of-thought needs a small set of worked examples for every distinct task; the work of writing and maintaining those examples does not scale across a large portfolio of tasks or a fast-changing product. Without exemplars, however, plain prompting collapses the reasoning into a single output token and quality drops sharply. The team needs a way to trigger step-by-step reasoning that does not depend on supplying task-specific worked solutions in the prompt.

Solution

Append a trigger phrase ('Let's think step by step', 'Let's work through this carefully') to the prompt. The model produces reasoning before its answer with no exemplar required. Optionally extract the final answer with a follow-up prompt.

When to use

• Reasoning tasks where curating few-shot exemplars is impractical or costly.
• A trigger phrase reliably elicits useful chains for the task domain.
• Latency budget allows the model to produce reasoning before the answer.