Unit 2 · Make AI outputs predictable

Describe inputs and outputs in one line

You can describe an ordinary typed contract in one readable line. Inputs go before the arrow and outputs go after it.

ax()5 focused minutesNot started

Worked example

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const extract = ax('email:string -> sender:string, topics:string[], needsReply:boolean');

Declare the source value
email is the string your application passes in.
List the result fields
The output side combines a string, an array, and a boolean.
Call it like a typed program
Ax uses this declaration to prompt, parse, and validate the response.

Run itIn your own project

npm install @ax-llm/ax

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

const llm = ai({ name: 'openai', apiKey: process.env.OPENAI_APIKEY! });
const classify = ax('review:string -> sentiment:class "positive, negative, neutral"');

const result = await classify.forward(llm, {
  review: 'Useful and boring in the best way.',
});

Set OPENAI_APIKEY in your environment before running provider-backed code.

In the ax repo

From a clone of the ax repo:

npm run example -- typescript src/examples/typescript/generation/structured.ts

Active practice

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Answer 2 in a row to learn this · attempt 1

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