UCP (Universal Commerce Protocol) and ACP (Agentic Commerce Protocol) are API specifications that enable "cart checkout in the AI prompt" or "seamless checkout" within ChatGPT and Gemini. As of early 2026, the primary use case for both is to create a more natural workflow when buying something directly through an AI chat interface:
UCP is led primarily by Google, while ACP is backed by OpenAI and Stripe. They achieve the same end goals and are functionally identical. Since one might eventually become the industry standard, you could wait for a winner, implement both, or choose based on your priority between Gemini and ChatGPT. Note that NONE of these are required to get your products into LLM conversations right now. They are simply add-on protocols that primarily enable the “checkout” functionality.
Beyond just checkout, Gemini and OpenAI may favor companies that adopt these protocols first (that is, they may give early access to some ads if you actually implement UCP or ACP). In addition, these APIs aim to eventually handle the full-product lifecycle -- discovery, cart, identity linking, and ordering. So in time, these protocols will allow AI agents to fully interact with your ecomm stack -- discovering products, vetting them for the consumer, calculating shipping, and finishing the transaction. For now, though, it is mostly just "checkout in the prompt."
This image shows the complete tech stack in more detail.
Technically, UCP and ACP are “API specifications”. Programmers will write code that adheres to the technical spec and then integrate it into your ecommerce stack. Most companies on platforms like Shopify, SFCC, BigCommerce, and others would just use a plugin, while enterprise firms on legacy systems may need to actually task developers to build UCP or ACP for their specific system. The code essentially opens an interface for third-party bots like Gemini or ChatGPT to interact with your store in a defined way. If you're not a dev, that all just means UCP/ACP enable bots to navigate your site like a human does, but as an AI assistant representing a real consumer via a LLM chat window.
If your company is trying to stay on top of the chaotic LLM product advertising options, consider talking with a VersaFeed rep. We've been playing the AI game for three years now and have deep roots in this field. We can advise on "how necessary" it is that you implement ACP or UCP at this time based on your specific goals and timelines.