Agentic Commerce: How to Prepare Your Online Store for AI Shopping Agents

Agentic commerce is shopping in which an AI assistant does part of the work a shopper used to do in a browser: it searches across stores, compares products against the shopper's request, and on some surfaces fills the cart and pays. The shopper approves; the agent handles the steps in between. For a store, the practical change is that a machine now reads your catalogue, prices, stock and policies before a person ever sees your site.

It helps to separate three layers, because each one has a different owner and a different level of maturity: discovery (can an agent find and correctly describe your product?), checkout (can the purchase be completed, and on whose page?) and payment authorization (how does the agent prove the shopper approved the charge?). Most of the confusion in 2026 coverage comes from treating these as one thing.

The Agentic Commerce Protocol (ACP) is an open standard for how AI agents and businesses complete purchases on behalf of buyers. Stripe's documentation describes it as created by Stripe, OpenAI and Meta, and its published specification is versioned by date, with the current OpenAPI and JSON Schema files under a 2026-04-17 release. ACP defines building blocks for agentic checkout sessions, catalogue feeds and carts, delegated payment through payment tokens, delegated authentication with OAuth 2.0, and order webhooks for confirmation, shipping, delivery and refunds.

Google's Universal Commerce Protocol (UCP) is an open-source standard that Google uses for native checkout in AI Mode in Google Search and the Gemini app. Google's merchant guide says UCP supports a REST API and an MCP binding, is compatible with the Agent Payments Protocol (AP2), Agent2Agent (A2A) and MCP, and can reuse existing Merchant Center shopping feeds. Account linking for loyalty programs, post-purchase tracking and returns, and multi-item carts are listed as upcoming rather than available.

The two protocols overlap more than they compete at the store level. Both assume the merchant keeps its own product data, prices and order system, and both need the same underlying facts from you. Choosing between them is usually decided by which commerce platform and payment provider you already use, not by the protocol itself.

The most important development of 2026 was a retreat. CNBC reported on March 20, 2026 that OpenAI was ending Instant Checkout, its in-chat purchase flow, and moving to retailer apps in ChatGPT where purchases complete on the retailer's own website. An OpenAI spokesperson said Instant Checkout was moving to Apps and that the company was prioritizing better search and product discovery. Shopify told CNBC that checkout would no longer be native in ChatGPT and that its merchants would not need to build ChatGPT apps to take part.

The same article reported Walmart data showing conversion rates three times lower for products sold directly inside ChatGPT than for products that sent users to a retailer's site to check out; Walmart had made about 200,000 products available there. Forrester's analysts, writing on March 7, 2026, noted that completing a purchase inside an answer engine was the least-adopted use case among regular users it surveyed in the US, UK and Canada, even though 23% of Gen X, 32% of Millennials and 35% of Gen Z respondents in its December 2025 survey had used ChatGPT to search for products in the past month.

The lesson for store owners: shoppers already use AI assistants to research products, but they still prefer to buy on a page they trust. Being found and described correctly is the near-term opportunity; in-chat payment is still settling.

Availability differs by platform and country, so check each channel's current documentation before planning. As of the pages we reviewed for this article:

An agent can only recommend what it can read and verify. Before any protocol work, the order we recommend is to make the catalogue machine-trustworthy. Every item below also improves Google Shopping, on-site search and ordinary SEO, so none of it is wasted if a channel changes course again.

Google states that you stay the merchant of record for UCP-powered checkout, and under ACP the agent creates and completes checkout sessions with the business's own systems. That means the customer service, refunds, chargebacks and tax obligations stay with you even when the order started in an assistant. Plan for these operational gaps before turning on direct checkout:

Forrester's advice after the ChatGPT reversal was to treat answer engines as one more digital channel with its own strategy, to avoid relying on any single channel, and to keep the checkout moment where possible. Applied to store type, that gives a simple sequence: