Agentic Commerce Protocol (ACP)

At its core, the Agentic Commerce Protocol (ACP) acts as a universal translator for the digital economy. It is an open standard, co-developed by OpenAI and Stripe and announced in September 2025, designed to bridge the gap between intelligent AI agents and the systems that power online stores. By providing a common set of rules, ACP allows an AI agent to understand a merchant’s inventory, manage a shopping cart, and finalize a purchase without the user ever needing to leave the AI interface.

Think of ACP like a standardized plug for an appliance. Just as you don’t need a different wall outlet for every brand of toaster, merchants don’t need to build a custom connection for every AI assistant. With a single backend integration, a merchant can make their products available to multiple AI agents simultaneously. This architecture covers the entire lifecycle of a transaction, including product discovery, cart management, secure checkout, and post-purchase operations.

The protocol ensures that merchants remain in the driver’s seat. Even when an AI agent facilitates the sale, the merchant remains the Merchant of Record. This means they retain full control over critical business functions, including pricing, brand presentation, order acceptance or decline, fulfillment, and returns [2].

The most prominent application of this protocol is ChatGPT Instant Checkout. This feature allows users to purchase products directly within their ChatGPT conversations. Following an initial launch with US Etsy sellers, the protocol has expanded to support over one million Shopify merchants, including brands like Glossier, Kitsch, Spanx, Vera Wang, and SKIMS [2]. Because the protocol is open-source on GitHub under Apache 2.0 [3], it is designed to be adopted across the broader ecosystem of AI-powered shopping, not just within OpenAI’s products.

For those exploring the future of digital retail, understanding ACP is essential to grasping how agentic commerce is evolving. It represents a shift from static, manual browsing to dynamic, AI-assisted purchasing. By standardizing how agents interact with merchant infrastructure, ACP helps move the industry toward a more integrated, efficient, and user-friendly experience.