Google just published details about its Universal Commerce Protocol (UCP), an open standard aimed at making shopping work natively with AI agents instead of websites. The idea is to standardize the entire commerce flow—product discovery, pricing, checkout, payment, and post-purchase—so an AI agent can complete purchases directly without custom integrations for every merchant. Merchants remain the seller of record, but expose capabilities through a common protocol, letting agents compare options and execute checkout across many stores. If this takes off, it weakens marketplace lock-in (including Amazon’s) by shifting discovery and checkout out of proprietary UIs and into AI-driven intent flows, similar to how open web protocols reduced the power of early internet portals.