Acp Handler

acp-handler

A TypeScript handler for implementing the [Agentic Commerce Protocol](https://developers.openai.com/commerce) (ACP) in your web application. Handle ACP checkout requests with built-in idempotency, signature verification, and OpenTelemetry tracing.

What is ACP?

An open standard for programmatic commerce flows between buyers, AI agents, and businesses. This package handles the protocol implementation so you can focus on your business logic.

**Key Features:**

• ✅ Full ACP spec compliance
• ✅ Type-safe TypeScript API
• ✅ Built-in idempotency (prevents double-charging)
• ✅ OpenTelemetry tracing support
• ✅ Web Standard APIs (works with Next.js, Hono, Express, Cloudflare Workers, Deno, Bun, Remix)
• ✅ Production-ready patterns
• ✅ Comprehensive test suite

Installation

pnpm add acp-handler

Peer Dependencies

The handler requires a key-value store for session storage. Redis is recommended:

pnpm add redis

Optional dependencies:

pnpm add next  # For Next.js catch-all route helper

Quick Start

1. Define Your ACP Handler

Create your ACP handler in a central location (e.g., `lib/acp.ts`) so you can reuse it throughout your app:

import { acpHandler, createStoreWithRedis } from 'acp-handler';

// Wire up storage (uses REDIS_URL environment variable)
const { store } = createStoreWithRedis('acp');

// Create ACP handler with business logic
const { handlers, webhooks, sessions } = acpHandler({
  // Product pricing logic
  products: {
    price: async ({ items, customer, fulfillment }) => {
      // Fetch products from your database
      const products = await db.products.findMany({
        where: { id: { in: items.map(i => i.id) } }
      });

      // Calculate pricing
      const itemsWithPrices = items.map(item => {
        const product = products.find(p => p.id === item.id);
        return {
          id: item.id,
          title: product.name,
          quantity: item.quantity,