Few-Shot Examples for Code

Anchor output shape with one or two input/output pairs before the real task.

Prompt EngineeringIntermediate

Why

GitHub's 2024 survey found 92% of US respondents use AI coding tools to generate test cases, and 73% of open source respondents use AI tools for coding or documentation. Zero-shot prompts drift across model versions; one concrete example pins the exact shape, naming, and style you want.

Few-shot is the highest-leverage block for consistent code output.

When

Use few-shot when output must match a strict shape (file template, API response) or when zero-shot drifts. Skip for open-ended exploration.

How

1. Pick one known-good example (input → output). 2. Place it before the real task in the prompt. 3. Keep the example minimal — trim anything not shape-relevant. 4. Use two examples only if one leaves ambiguity. 5. Reference it: "follow the shape of the example above".

Example

Example (in prompt): Input: "POST /health" Output: export const POST = async (c) => c.json({ ok: true }, 200); Task: "POST /books — follow the shape above, validate body with zod, persist." Output matches the named-export + c.json shape exactly.

Common Problems

⚠Error: Model returns "I cannot help with that" → rephrase to remove restricted phrasing; narrow scope and provide explicit allowed examples.
⚠JSON parse error on model output → wrap with a fenced ```json block and add "respond with valid JSON only" to the system prompt.
⚠Error: Token limit exceeded (400 Bad Request) → split the prompt, summarize prior context, or switch to a larger context model.

Best Practices

✓Use exactly one minimal example unless ambiguity remains.
✓Trim the example to only shape-relevant lines.
✓Measure the outcome with a concrete metric (time saved, defect rate, test coverage) so the practice can be justified and improved.

FAQ

What is Few-Shot Examples for Code?

Anchor output shape with one or two input/output pairs before the real task. It helps developers quickly grasp the core value and use cases of Few-Shot Examples for Code.

How do I get started with Few-Shot Examples for Code?

To get started with Few-Shot Examples for Code, focus on these points first: Pick one known-good example (input → output).

What are common mistakes with Few-Shot Examples for Code?

Common mistakes when using Few-Shot Examples for Code include: Error: Model returns "I cannot help with that" → rephrase to remove restricted phrasing; narrow scope and provide explicit allowed examples.; JSON parse error on model output → wrap with a fenced ```json block and add "respond with valid JSON only" to the system prompt.; Error: Token limit exceeded (400 Bad Request) → split the prompt, summarize prior context, or switch to a larger context model..

What are the best practices for Few-Shot Examples for Code?

Best practices for Few-Shot Examples for Code include: Use exactly one minimal example unless ambiguity remains.; Trim the example to only shape-relevant lines.; Measure the outcome with a concrete metric (time saved, defect rate, test coverage) so the practice can be justified and improved..

How do I learn more about Few-Shot Examples for Code?

Start with the official docs, then search real-world examples on GitHub. Validate patterns in a small scratch repo before applying them to production code.