examples

Promptfmt Examples

This directory contains example files demonstrating various use cases of the promptfmt library.

Running Examples

First, build the package:

npm run build

Then run examples using one of these methods:

Method 1: Using ts-node (Recommended)

# Install ts-node if not already installed
npm install -g ts-node

# Run an example
npx ts-node -r tsconfig-paths/register examples/01-basic-usage.ts

# Or run all examples
npx ts-node -r tsconfig-paths/register examples/run-all.ts

Method 2: Using Node with compiled output

# Build the package first
npm run build

# Examples import from src, so they need to be run with ts-node
# or you can modify imports to use '../dist' after building

Method 3: Import in your own code

After installing the package, you can import and use it:

import { PromptBuilder } from 'promptfmt';

const prompt = new PromptBuilder()
  .role('You are a helper')
  .goal('Help users')
  .build();

Example Files

01-basic-usage.ts

Demonstrates the simplest way to use promptfmt with basic components (role, goal, input, output).

02-parameter-substitution.ts

Shows how to use template strings with ${paramName} syntax and function-based dynamic content.

03-conditional-logic.ts

Demonstrates conditional logic to include/exclude components based on runtime parameters.

04-component-ordering.ts

Shows how to control the order of components using the order option.

05-complex-example.ts

A sophisticated code review assistant that adapts based on programming language, code complexity, reviewer expertise level, and focus areas. Shows advanced conditional logic, dynamic content, and real-world complexity.

06-all-components.ts

Demonstrates all available component types in a single prompt (role, goal, context, input, persona, tone, tasks, steps, few-shots, guardrails, constraints, output).

07-custom-labels.ts

Shows how to use custom labels for components to create more structured and readable prompts.

08-dynamic-content.ts

Demonstrates using functions for dynamic content generation based on parameters.

Key Concepts

Parameter Substitution

Use ${paramName} in template strings:

.role('Hello ${name}')

Function-based Content

Use functions for dynamic content:

.role((params) => `Hello ${params.name}`)

Conditional Logic

Include components conditionally:

.persona('Persona A', {
  condition: createCondition(
    (params) => params.age > 18,
    new PersonaComponent('Adult Persona'),
    new PersonaComponent('Child Persona')
  )
})

Component Ordering

Control component order:

.role('Role', { order: 1 })
.goal('Goal', { order: 2 })

Custom Labels

Add custom labels:

.role('Role', { label: '🎭 ROLE' })