Agentic Commerce Protocol (ACP)
Agentic Commerce Protocol (ACP) is OpenAI's protocol enabling AI agents to complete purchases on behalf of users. Built on Stripe's Secure Payment Token (SPT) framework, ACP allows ChatGPT and other AI agents to negotiate, confirm, and settle transactions entirely programmatically.
What is ACP?
Agentic Commerce Protocol (ACP) is OpenAI's answer to the question: once an AI agent has discovered a product (via UCP), how does it actually buy it? ACP defines the full checkout execution layer — the structured APIs, authentication flows, and payment primitives that allow AI agents to complete purchases programmatically, without requiring human navigation of checkout pages, form fills, or CAPTCHA challenges.
At the heart of ACP is the Stripe Secure Payment Token (SPT). When a user authorizes ChatGPT (or any ACP-compatible agent) to make purchases on their behalf, Stripe issues a cryptographically signed, scoped payment token. This token encodes the user's pre-authorized spending limits, permitted merchant categories, and time validity window. The AI agent presents this token at checkout — the merchant validates it with Stripe and completes the charge — without the user ever entering their card number.
ACP is not just a payment protocol — it's a complete commerce execution specification. It defines how agents ingest product feeds, query real-time inventory and pricing, create shopping carts via structured API calls, apply discount codes and loyalty rewards, select shipping methods from pre-stored profiles, and receive structured order confirmations that can be parsed, stored, and acted upon by downstream agents.
For merchants, ACP compliance means your checkout flow is accessible to every AI shopping agent built on OpenAI's ecosystem — including ChatGPT Instant Checkout, enterprise procurement agents, and autonomous resupply systems. With ChatGPT alone serving over 400 million weekly active users as of early 2026, ACP non-compliance is an increasingly costly blind spot.
How ACP Works: The Agent Checkout Flow
ACP defines a four-step checkout execution flow. Every ACP-compatible merchant exposes these endpoints, and every ACP-compatible agent follows this sequence.
ACP Checkout API Example
// ACP Checkout Flow — Step by Step
// 1. Agent fetches product catalog
GET /api/acp/v1/products?q=wireless+headphones&limit=5
Authorization: Bearer {merchant_api_key}
// 2. Agent creates a cart
POST /api/acp/v1/carts
{
"items": [
{ "product_id": "prod_abc123", "quantity": 1 }
],
"agent_id": "chatgpt-shopping-agent",
"buyer_locale": "en-US"
}
// Response: Cart with price breakdown
{
"cart_id": "cart_xyz789",
"subtotal": 24900,
"tax": 1992,
"shipping": 0,
"total": 26892,
"currency": "USD"
}
// 3. Agent presents Stripe SPT for payment
POST /api/acp/v1/carts/cart_xyz789/checkout
{
"payment": {
"type": "stripe_spt",
"token": "spt_live_xxxxxxxxxx"
},
"shipping": {
"profile_id": "ship_profile_abc",
"method": "standard"
}
}
// 4. Order confirmation
{
"order_id": "ord_9876",
"status": "confirmed",
"estimated_delivery": "2026-03-04",
"confirmation_email": "buyer@example.com"
}ACP vs Traditional Checkout
| Factor | Traditional Checkout | ACP Agent Checkout |
|---|---|---|
| Time to complete | 3-8 minutes (manual) | < 10 seconds (automated) |
| Human required | Yes — every step | No — fully autonomous |
| Abandoned cart risk | High (70% avg) | Near zero |
| Payment method | Card entry per transaction | Pre-authorized SPT (zero friction) |
| Cart persistence | Session-based (lost on close) | Server-side (persistent) |
| Order confirmation | Email HTML (unstructured) | Structured JSON (machine-readable) |
| Multi-merchant purchasing | Requires separate sessions | Single agent orchestration |
| Loyalty / discount application | Manual code entry | Automatic via agent profile |
Benefits of ACP Integration
ChatGPT Instant Checkout
ACP compliance makes your products purchasable through ChatGPT Instant Checkout — reaching hundreds of millions of users without any additional marketing spend.
Zero Abandonment
AI agents don't get distracted, run out of patience, or encounter UX friction. ACP-initiated checkouts complete at rates traditional e-commerce can't approach.
Enterprise Procurement
Enterprise procurement agents are the fastest-growing ACP use case. ACP compliance means your catalog is accessible to autonomous corporate purchasing systems.
Ready to Enable ACP Checkout?
Adam Silva Consulting implements the complete ACP stack — product feed configuration, cart and checkout API endpoints, Stripe SPT integration, and ChatGPT Merchant Center enrollment. We handle the technical complexity so your team can focus on inventory and fulfillment. Most ACP integrations go live within 4-6 weeks.
Agentic Commerce Protocol FAQ
What is Agentic Commerce Protocol (ACP)?+
Agentic Commerce Protocol (ACP) is OpenAI's protocol enabling AI agents to complete purchases on behalf of users. Built on Stripe's Secure Payment Token (SPT) framework, ACP allows ChatGPT and other AI agents to negotiate, confirm, and settle transactions entirely programmatically.
What is a Stripe Secure Payment Token (SPT)?+
A Stripe Secure Payment Token (SPT) is an encrypted, single-use payment credential that an AI agent holds on behalf of a user. When the user authorizes ChatGPT or another ACP-compatible agent to make purchases, Stripe issues an SPT that the agent can use to complete transactions without exposing raw card data. The token is scoped to specific merchant categories, spending limits, and time windows.
Is ACP the same as ChatGPT Instant Checkout?+
ChatGPT Instant Checkout is the consumer-facing feature built on top of ACP. The Agentic Commerce Protocol is the underlying technical specification that defines how ChatGPT communicates with merchants during checkout — the product feed format, cart creation API, payment token presentation, and order confirmation flow. ACP is the protocol; Instant Checkout is the user experience.
Do I need Stripe to implement ACP?+
The current ACP specification is tightly integrated with Stripe's SPT framework for payment handling. However, ACP-compatible implementations can use other payment processors for the underlying charge — the SPT is the AI-layer abstraction that sits above your existing payment infrastructure. Most merchants implement ACP by adding Stripe as a secondary payment processor to handle agent-initiated transactions.
How does ACP differ from traditional checkout?+
Traditional checkout requires a human to navigate product pages, add items to a cart, enter shipping and payment details, and click a confirm button. ACP eliminates every manual step. An ACP-enabled AI agent receives product recommendations, creates a cart via API, presents a pre-authorized SPT for payment, confirms shipping from a stored profile, and places the order — in under 10 seconds, without the user ever visiting your website.
Enable AI Agent Checkout Today
ACP is how AI agents buy from merchants. If you're not ACP-compliant, agents can't purchase your products — no matter how good your catalog is.
Talk to Adam About ACP