Ax: Build Reliable AI Apps in TypeScript

Stop wrestling with prompts. Start shipping AI features.

Ax brings DSPy’s revolutionary approach to TypeScript – just describe what you want, and let the framework handle the rest. Production-ready, type-safe, and works with all major LLMs.

Transform Your AI Development in 30 Seconds

import { ai, ax } from "@ax-llm/ax";

// 1. Pick any LLM
const llm = ai({ name: "openai", apiKey: process.env.OPENAI_APIKEY! });

// 2. Say what you want
const classifier = ax(
  'review:string -> sentiment:class "positive, negative, neutral"',
);

// 3. Get type-safe results
const result = await classifier.forward(llm, {
  review: "This product is amazing!",
});
console.log(result.sentiment); // "positive" ✨

That’s it. No prompt engineering. No trial and error. It works with GPT-4, Claude, Gemini, or any LLM.

Why Thousands of Developers Choose Ax

🎯 Define Once, Run Anywhere

Write your logic once. Switch between OpenAI, Anthropic, Google, or 15+ providers with one line. No rewrites needed.

⚡ Ship 10x Faster

Stop tweaking prompts. Define inputs → outputs. The framework generates optimal prompts automatically.

🛡️ Production-Ready from Day One

Built-in streaming, validation, error handling, observability. Used by startups in production handling millions of requests.

🚀 Gets Smarter Over Time

Train your programs with examples. Watch accuracy improve automatically. No ML expertise needed.

Real Apps, Real Simple

Extract Structured Data from Customer Emails

const extractor = ax(`
  customerEmail:string, currentDate:datetime -> 
  priority:class "high, normal, low",
  sentiment:class "positive, negative, neutral",
  ticketNumber?:number,
  nextSteps:string[],
  estimatedResponseTime:string
`);

const result = await extractor.forward(ai, {
  customerEmail: "Order #12345 hasn't arrived. Need this resolved immediately!",
  currentDate: new Date(),
});
// Automatically extracts all fields with proper types and validation

Build Agents That Use Tools (ReAct Pattern)

const assistant = ax(
  "question:string -> answer:string",
  {
    functions: [
      { name: "getCurrentWeather", func: weatherAPI },
      { name: "searchNews", func: newsAPI },
    ],
  },
);

const result = await assistant.forward(ai, {
  question: "What's the weather in Tokyo and any news about it?",
});
// AI automatically calls both functions and combines results

const analyzer = ax(`
  image:image, question:string ->
  description:string,
  mainColors:string[],
  category:class "electronics, clothing, food, other",
  estimatedPrice:string
`);
// Process images and text together seamlessly

Quick Start

Install

npm install @ax-llm/ax

Your First AI Feature (2 minutes)

import { ai, ax } from "@ax-llm/ax";

const llm = ai({ name: "openai", apiKey: process.env.OPENAI_APIKEY! });

const translator = ax(`
  text:string, 
  language:string -> 
  translation:string
`);

const result = await translator.forward(llm, {
  text: "Hello world",
  language: "Spanish",
});
console.log(result.translation); // "Hola mundo"

Powerful Features, Zero Complexity

✅ 15+ LLM Providers - OpenAI, Anthropic, Google, Mistral, Ollama, and more
✅ Type-Safe Everything - Full TypeScript support with auto-completion
✅ Streaming First - Real-time responses with validation
✅ Multi-Modal - Images, audio, text in the same signature
✅ Smart Optimization - Automatic prompt tuning with MiPRO
✅ Production Observability - OpenTelemetry tracing built-in
✅ Advanced Workflows - Compose complex pipelines with AxFlow
✅ Enterprise RAG - Multi-hop retrieval with quality loops
✅ Agent Framework - Agents that can use tools and call other agents
✅ Zero Dependencies - Lightweight, fast, reliable

Learn More

🚀 Quick Wins

Getting Started Guide - Set up in 5 minutes
Examples Guide - Comprehensive examples with explanations
DSPy Concepts - Understand the revolutionary approach

📚 Deep Dives

AxFlow Workflows - Build complex AI systems
Optimization Guide - Make your programs smarter
Advanced RAG - Production search & retrieval
API Reference - Complete documentation

Examples

Run any example:

OPENAI_APIKEY=your-key npm run tsx ./src/examples/[example-name].ts

Core Examples

extract.ts - Extract structured data from text
react.ts - ReAct pattern with function calling
agent.ts - Multi-agent collaboration
streaming1.ts - Real-time streaming responses
multi-modal.ts - Image + text processing

Production Patterns

customer-support.ts - Complete support system
food-search.ts - Restaurant recommendations with tools
simple-optimizer-test.ts - Automatic optimization
mipro-python-optimizer.ts - Advanced MIPRO optimization
ax-flow-enhanced-demo.ts - Complex workflows

📚 View Full Examples Guide →
View All 70+ Examples →

Join the Community

🐦 Follow on Twitter - Latest updates
💬 Discord Community - Get help, share ideas
⭐ Star on GitHub - Support the project
📖 Ask DeepWiki - AI-powered docs

Production Ready

✅ Battle-tested - Used by startups in production
✅ No breaking changes - Stable minor versions
✅ Comprehensive tests - Large test coverage
✅ OpenTelemetry - Built-in observability
✅ TypeScript first - Type-safe by design

License

MIT - Use it anywhere, build anything.

Ready to build the future? Stop fighting with prompts. Start shipping with signatures.

npm install @ax-llm/ax

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