OpenAI’s retreat was likely a result of the “Synchronization Lag.” To make AI checkout work, you need millisecond-accurate data on price, inventory, and tax across millions of stores. For a software-first company like OpenAI, building that bridge from scratch is an immense engineering hurdle.
Google, however, did not build a new bridge. They simply upgraded the one they already had: the Google Merchant Center.
By embedding UCP onboarding into the Merchant Center, Google did not ask retailers to build a new tech stack. They simply asked them to “turn on” a new language for their existing data. This move positions UCP less like a product launch and more like a new handshake. The moment two systems agree on a shared language, everything built on top of it just works. And crucially, it is an open standard, meaning no single company owns the protocol. It allows any AI agent to talk to any merchant backend, ensuring that the buy button actually works every single time.
