Prompt Composer

A modular system prompt composition framework that intelligently generates system prompts for AI assistants based on available tools, task complexity, and contextual information.

Language Support

• Python: pip install system-prompt-composer
• Node.js: npm install system-prompt-composer (native bindings - no Python required!)

Quick Start

Python

import system_prompt_composer
import json

request = {
    "user_prompt": "Help me analyze this code",
    "mcp_config": {"mcpServers": {...}},
    "session_state": {"tool_call_count": 0}
}

response = system_prompt_composer.compose_system_prompt(json.dumps(request))
result = json.loads(response)
print(result["system_prompt"])

Node.js (Native)

const { composeSystemPrompt } = require('system-prompt-composer');

const request = {
  user_prompt: "Help me analyze this code",
  mcp_config: { mcpServers: {...} },
  session_state: { tool_call_count: 0 }
};

const response = await composeSystemPrompt(request);
console.log(response.system_prompt);

📖 For detailed Node.js documentation, see node/README.md

Project Structure

prompt-composer/
├── core/              # Rust core implementation
│   ├── lib.rs         # Main library with NAPI bindings
│   ├── types.rs       # Type definitions
│   ├── composition.rs # Prompt composition logic
│   └── ...
├── python/            # Python package (PyO3 bindings)
├── node/              # Node.js package (native NAPI-RS bindings)
│   ├── package.json
│   ├── index.js       # Native bindings wrapper
│   └── index.d.ts     # TypeScript definitions
├── prompts/           # Modular prompt library
│   ├── domains/       # Domain-specific prompts
│   └── behaviors/     # Behavioral guidance prompts
└── README.md          # This file

Features

• 🧠 Intelligent prompts that adapt to available MCP tools
• 📋 Automatic task planning for complex requests
• 🎯 Context-aware guidance for different domains (programming, analysis, filesystem, etc.)
• 📊 Progress monitoring for multi-step workflows
• 🔄 Modular design with composable prompt components
• ⚡ High performance with Rust core
• 🌍 Multi-language support (Python, Node.js)

Installation

Python Package

pip install system-prompt-composer

Node.js Package (Native - No Python Required!)

npm install system-prompt-composer

The Node.js package now uses native Rust bindings via NAPI-RS, eliminating the Python dependency!

API Reference

Core Functions

composeSystemPrompt(request)

Generate an intelligent system prompt based on available tools and context.

Parameters:

• request.user_prompt (string): The user's request
• request.mcp_config (object): MCP server configuration with mcpServers
• request.session_state (object): Current session state including tool_call_count
• request.domain_hints (array, optional): Domain hints like ["programming", "analysis"]
• request.task_complexity (string, optional): "Simple", "Complex", or "Auto"

Returns:

{
  system_prompt: "Generated prompt text...",
  source: "native",
  version: "1.1.0",
  // ... additional metadata
}

listAvailableDomains()

Returns array of available domain modules: ["programming", "analysis", "filesystem", "system"]

listAvailableBehaviors()

Returns array of available behavior modules: ["planning", "progress", "reasoning", "tools"]

getStatus()

Returns system status and configuration information.

isAvailable()

Always returns true for native bindings.

Architecture

Native Node.js Architecture (NEW):

Node.js → NAPI-RS → Rust Core

Python Architecture:

Python → PyO3 → Rust Core  

Key Benefits of Native Bindings:

• ✅ No Python dependency for Node.js users
• ✅ Native performance - direct Rust execution
• ✅ Simple deployment - just npm install
• ✅ Better error handling
• ✅ Cross-platform binary distribution
• ✅ Smaller bundle size

Development

Building Native Node.js Package

cd node/
npm install
npm run build        # Build release binaries
npm run build:debug  # Build debug binaries
npm test            # Run tests

Python Development

cd python/
pip install -e .

Rust Core Development

cargo build --release
cargo test
cargo build --features nodejs  # For Node.js bindings
cargo build --features python  # For Python bindings

Publishing

Node.js (npm)

cd node/
npm run build       # Build native binaries
npm publish --access public

Python (PyPI)

cd python/
pip install build twine
python -m build
twine upload dist/*

Contributing

Contributions welcome! The project uses:

• Rust for the core prompt composition engine
• NAPI-RS for Node.js native bindings
• PyO3 for Python bindings
• Modular prompts in the prompts/ directory

License

MIT License - see LICENSE file for details.