AG2B

AG2B (Agent to Browser) is a client-side agentic runtime.

The agent runs where your app does — in the browser. The server's role can range from a thin LLM proxy to a layer that extends the client runtime.

Warning

AG2B is under active development — the public API can shift between minor releases. Check release notes before upgrading.

Important

Full documentation lives at ag2b.ai.

What you get

🧩 Agent primitives — Building blocks that live next to your components and stores.
🛡️ End-to-end typed tools — Zod schemas validate at runtime and type your handler.
🔄 Open lifecycle — Observe or intercept every boundary in the loop.
🔌 Provider-agnostic — Swap LLM providers with one line — built-in or your own.
📦 Plain TypeScript core — No framework lock-in. Drop it into anything.
🧱 Framework bindings — Per-framework bindings.

Quickstart

Install

npm i @ag2b/core zod

Writing your first agent

import { Agent, OpenAiProvider, Scope, Tool } from '@ag2b/core';
import { z } from 'zod/v4';

const setBackground = new Tool({
  name: 'setBackground',
  description: 'Change the page background color.',
  parameters: z.object({ color: z.string() }),
  handler: ({ color }) => {
    document.body.style.backgroundColor = color;
  },
});

const agent = new Agent({
  provider: new OpenAiProvider({ baseURL: '/api/llm' }),
});

agent.scopes.register(new Scope({ name: 'appearance', tools: [setBackground] }));

await agent.chat('Make the page feel like a sunset.');
// → the LLM picks a color, the tool runs, the page changes.

License

MIT