Unit 5 · Build an agent that can use tools

Let an agent investigate and act

You give a typed task an iterative runtime where the model can inspect evidence, call tools, and delegate. It still finishes through your declared output contract.

agent()8 focused minutesNot started

Worked example

See the idea in context

const helper = agent('request:string -> resolution:string', { functions: [search] });
const result = await helper.forward(llm, { request });

Declare the whole task
The signature keeps the request and final resolution typed.
Provide allowed capabilities
functions limits the tools the runtime may choose.
Start one agent run
forward() lets the agent inspect, act, and finish with a resolution.

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/short-agents/tools-agent.ts

Active practice

Show that you can use it

Answer 2 in a row to learn this · attempt 1

Keep exploring

See the idea in context

Show that you can use it

Source-backed follow-up