Few-Shot Prompt Builder

Create few-shot learning prompts with example input-output pairs

Task Description

Example Pairs (1)

Example 1

Output Format

Generated Prompt

[
  {
    "role": "system",
    "content": "You are a helpful assistant."
  }
]
79 characters ~16 tokens

Few-Shot Tips

  • 3-5 examples is usually optimal for most tasks
  • Include diverse examples that cover edge cases
  • Keep examples consistent in format and length
  • Put your best, clearest examples first

Related Tools

Complete Guide to Few-Shot Learning Prompts

How to Use This Tool

The Few-Shot Prompt Builder helps you create effective few-shot learning prompts by structuring example input-output pairs. Follow these steps:

1

Describe Your Task

Enter a clear description of the task you want the AI to perform. This helps the model understand the context and expected behavior. For example: "Classify customer reviews as positive or negative."

2

Add Example Pairs

Create input-output example pairs that demonstrate the desired behavior. Each example should show an input and the corresponding expected output. Click "Add Example" to create more pairs.

3

Choose Output Format

Select the format for your prompt: Chat Messages (JSON array for chat APIs), Completion (text-based format), or XML Tags (structured markup for Claude). Each format has different use cases.

4

Copy or Download

Review the generated prompt in the output panel. Copy it to your clipboard or download it as a file. The token estimate helps you understand the cost impact.

What is Few-Shot Learning?

Few-shot learning is a prompting technique where you provide the AI model with a small number of examples (typically 2-10) to demonstrate the desired behavior before asking it to perform the task on new inputs. This approach is remarkably effective because it:

  • Improves accuracy: Examples help the model understand exactly what format and style of output you expect.
  • Reduces ambiguity: Showing is often clearer than telling when it comes to AI instructions.
  • Handles format consistency: Examples establish the output format implicitly.
  • Enables complex tasks: Some tasks that are hard to describe become easy to demonstrate.

How Many Examples Do You Need?

Task ComplexityRecommended ExamplesExample Tasks
Simple1-2Yes/no classification, simple extraction
Moderate3-5Sentiment analysis, categorization, formatting
Complex5-10Multi-step reasoning, specialized domains
Nuanced10+Edge cases, subtle distinctions, style matching

Output Format Comparison

Chat Messages

JSON array format compatible with OpenAI and similar chat APIs. Best for conversational AI applications.

  • OpenAI Chat API
  • Claude Messages API
  • Multi-turn conversations

Completion

Plain text format with labeled examples. Works with any text completion model or simple prompts.

  • Legacy Completion APIs
  • Simple integrations
  • Human readable

XML Tags

Structured XML format that Claude models particularly excel at parsing and following.

  • Claude models
  • Structured extraction
  • Clear boundaries

Best Practices for Examples

Creating Effective Examples

  • Be diverse: Include examples that cover different scenarios and edge cases.
  • Stay consistent: Use the same format and style across all examples.
  • Start with the clearest: Put your best, most unambiguous examples first.
  • Match real inputs: Examples should resemble the actual inputs you'll process.
  • Include edge cases: Show how to handle tricky or boundary situations.
  • Keep it concise: Long examples consume tokens without adding value.

Common Few-Shot Use Cases

Classification

Categorize text into predefined classes (sentiment, topic, intent).

Extraction

Pull specific information from unstructured text (names, dates, entities).

Transformation

Convert text from one format/style to another (rewriting, translation).

Reasoning

Demonstrate step-by-step thinking for complex problem solving.

Few-Shot vs Zero-Shot vs Fine-Tuning

When to Use Each Approach

  • Zero-shot: Simple, well-defined tasks that the model already understands (translation, summarization).
  • Few-shot: Custom tasks, specific formats, domain-specific behavior, or when examples clarify ambiguity.
  • Fine-tuning: Very high volume (1000s of requests/day), consistent specialized behavior, or latency-sensitive applications.

Token Efficiency

Few-shot examples consume tokens with every request. To optimize costs:

  • Use the minimum number of examples needed for consistent results.
  • Keep examples as short as possible while remaining clear.
  • Consider caching or system prompts for frequently used examples.
  • Test with 2-3 examples first, then add more only if accuracy improves.