Glossary
Universal Commerce Protocol (UCP)
UCP (Universal Commerce Protocol) is Google's proposed standardized protocol that enables AI agents to complete commercial transactions on behalf of users across participating merchants and platforms. Announced at Google Marketing Live 2026 alongside complementary tools including a Universal Cart and agentic commerce APIs, UCP defines a common language for product discovery, cart management, payment processing, and order fulfillment that AI agents can navigate programmatically. The protocol represents Google's bet on an agentic commerce future where AI assistants — rather than humans — browse, compare, and purchase products across the web. For marketers, UCP signals a fundamental shift in the purchase journey: instead of optimizing for human shoppers navigating ecommerce sites and product listing ads, brands must prepare for AI agents that consume structured product data, evaluate options against user preferences, and execute transactions autonomously. UCP is Google's counterpart to OpenAI's Agentic Commerce Protocol (ACP), forming competing standards in the emerging agent-mediated commerce landscape.