Promptel

The first Node.js framework with native Harmony Protocol support for advanced prompt engineering. Supports both .prompt and .yml formats.

Why Promptel?

Modern AI applications need sophisticated prompt engineering, but implementing advanced techniques like Chain-of-Thought or handling multi-channel responses is complex and error-prone. Promptel solves this with a declarative approach and native support for OpenAI's Harmony Protocol.

Key Problems Solved

• Harmony Protocol Complexity: Only Node.js framework with native gpt-oss support
• Advanced Reasoning Techniques: Built-in Chain-of-Thought, Tree-of-Thoughts, ReAct
• Multi-Channel Responses: Automatic parsing of analysis, commentary, and final outputs
• Provider Lock-in: Abstract across OpenAI, Anthropic, Groq with consistent APIs

Quick Start

Installation

npm install promptel

Basic Example (.prompt format)

import { parsePrompt, executePrompt } from 'promptel';

const prompt = parsePrompt(`
prompt MathSolver {
  params {
    problem: string
  }

  body {
    text\`Solve: \${params.problem}\`
  }

  technique {
    chainOfThought {
      step("Analysis") { text\`Break down the problem\` }
      step("Solution") { text\`Calculate step by step\` }
      step("Verification") { text\`Verify the answer\` }
    }
  }
}
`);

const result = await executePrompt(prompt, {
  problem: "What is 25% of 240?"
}, {
  provider: 'openai',
  apiKey: process.env.OPENAI_API_KEY
});

console.log(result);

Harmony Protocol Example (gpt-oss)

const harmonyPrompt = parsePrompt(`
prompt HarmonyReasoning {
  harmony {
    reasoning: "high"
    channels: ["final", "analysis", "commentary"]
  }

  params {
    question: string
  }

  body {
    text\`\${params.question}\`
  }
}
`);

const result = await executePrompt(harmonyPrompt, {
  question: "Optimize database query performance for large datasets"
});

// Multi-channel outputs automatically parsed
console.log(result.channels.final);      // Clean answer for users
console.log(result.channels.analysis);   // Detailed reasoning process
console.log(result.channels.commentary); // Verification and alternatives

YAML Format Example

The same prompts can be written in YAML format for those who prefer structured configuration:

name: MathSolver

params:
  problem:
    type: string
    required: true

body:
  text: "Solve: ${params.problem}"

technique:
  chainOfThought:
    steps:
      - name: "Analysis"
        text: "Break down the problem"
      - name: "Solution"
        text: "Calculate step by step"
      - name: "Verification"
        text: "Verify the answer"

// Works with both formats automatically
const yamlPrompt = fs.readFileSync('math_solver.yml', 'utf-8');
const result = await executePrompt(yamlPrompt, { problem: "What is 25% of 240?" });

Format Conversion

Convert between .prompt and .yml formats:

# Convert .prompt to YAML
promptel --convert yaml -f solver.prompt -o solver.yml

# Convert YAML to .prompt
promptel --convert prompt -f solver.yml -o solver.prompt

// Programmatic conversion
import { FormatConverter } from 'promptel';

const converter = new FormatConverter();
const yamlVersion = converter.promptToYaml(promptContent);
const promptVersion = converter.yamlToPrompt(yamlContent);

Architecture

┌─────────────────┐    ┌─────────────────┐    ┌─────────────────┐
│  Parser Module  │    │ Executor Module │    │Provider Adapter │
│                 │    │                 │    │                 │
│ • Lexer/Parser  │◄──►│ • Harmony Integ │◄──►│ • OpenAI        │
│ • AST Builder   │    │ • Technique Eng │    │ • Anthropic     │
│ • Validation    │    │ • Output Format │    │ • Groq          │
└─────────────────┘    └─────────────────┘    └─────────────────┘

Flow: .prompt/.yml file → Parser → AST → Executor → Provider → LLM → Response Parser → Structured Output

Advanced Features

Multi-Provider Support

// Same prompt, different optimizations per provider
const executor = new PromptelExecutor(process.env.LLM_PROVIDER);
const result = await executor.execute(prompt, params);

// Harmony channels for OpenAI gpt-oss
// Thinking tags for Anthropic Claude
// Custom reasoning for Groq models

Built-in Techniques

• Chain of Thought: Step-by-step reasoning
• Tree of Thoughts: Multiple solution paths
• ReAct: Reasoning + Action planning
• Self-Consistency: Multi-solution consensus

Type-Safe Parameters

params {
  temperature: number = 0.7
  max_tokens?: number
  difficulty: "easy" | "medium" | "hard"
}

CLI Usage

# Execute prompt file (.prompt format)
promptel -f solver.prompt -p openai -k $OPENAI_API_KEY --params '{"problem":"2+2"}'

# Execute YAML format
promptel -f solver.yml -p openai -k $OPENAI_API_KEY --params '{"problem":"2+2"}'

# With output file
promptel -f prompt.prompt -p anthropic -k $ANTHROPIC_KEY -o result.json

# Convert formats
promptel --convert yaml -f solver.prompt -o solver.yml
promptel --convert prompt -f solver.yml -o solver.prompt

Requirements

• Node.js 18+ (LTS recommended)
• Supported provider API key (OpenAI, Anthropic, or Groq)

Documentation

• Technical Overview - Architecture and implementation details
• Harmony Design - OpenAI Harmony Protocol integration
• Grammar Reference - Complete language specification
• Dual Format Guide - Complete .prompt ↔ .yml format guide
• Development Tasks - Project roadmap and tasks

Contributing

We welcome contributions! Please see our development setup:

git clone https://github.com/terraprompt/promptel.git
cd promptel
npm install
npm test
npm run lint

Performance

| Operation | Time (ms) | Memory (MB) | |-----------|-----------|-------------| | Parse prompt | 5-15 | 2-5 | | Execute simple | 200-800 | 5-10 | | Execute complex | 1000-3000 | 10-20 | | Harmony parsing | 50-150 | 8-15 |

License

MIT License - see LICENSE file for details.

Support

• Documentation: Technical docs
• Issues: GitHub Issues
• Discussions: GitHub Discussions

Promptel makes advanced prompt engineering accessible, maintainable, and scalable for production AI applications.