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.

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.

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

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

Ax stays in the same latency class as direct provider calls while adding typed outputs, validation, retries, tracing, and tools. Streaming is the default so Ax can parse fields as they arrive, fail early on streaming assertions, cancel bad outputs, and start correction without wasting tokens on completions that are already invalid.

Benchmark the current code against your own providers:

AX_STREAM_BENCH_PROVIDER=anthropic AX_STREAM_BENCH_MODEL=claude-sonnet-4-5-20250929 AX_STREAM_BENCH_RUNS=2 AX_STREAM_BENCH_WARMUP_RUNS=0 npm run tsx src/examples/streaming-latency.ts
AX_STREAM_BENCH_PROVIDER=google-gemini AX_STREAM_BENCH_MODEL=gemini-3.5-flash AX_STREAM_BENCH_RUNS=2 AX_STREAM_BENCH_WARMUP_RUNS=0 npm run tsx src/examples/streaming-latency.ts

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

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

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

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

npm install @ax-llm/ax

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"

• ✅ Model-Lab Providers - OpenAI, Anthropic, Google, Mistral, DeepSeek, Grok/xAI, 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 GEPA and bootstrap demos
• ✅ Production Observability - OpenTelemetry tracing built-in
• ✅ Advanced Workflows - Compose complex pipelines with AxFlow
• ✅ Agent Framework - Agents that can use tools and call other agents
• ✅ Zero Dependencies - Lightweight, fast, reliable

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

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

Run any example:

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

• 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

• customer-support.ts - Complete support system
• food-search.ts - Restaurant recommendations with tools
• optimize.ts - Automatic optimization
• axagent-gepa-optimization.ts - Agent optimization with GEPA
• ax-flow-enhanced-demo.ts - Complex workflows

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

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

• ✅ 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

Apache 2 - 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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