How I Built Autonomous AI Purchasing on WooCommerce: OAuth 2.0, Identity Linking, and Wallet Payments

An AI agent searched a 40,000-SKU store, identified a product, pre-populated the buyer's details from a linked identity, debited a wallet, and created a paid WooCommerce order — with zero human interaction after the initial consent screen. This is what I built this week. Here's how it works. The Problem: AI Agents Can't Authenticate as Customers AI agents can already browse your store, read product listings, and build a cart. That part is solved by protocols like UCP (Universal Commerce Protocol) and MCP (Model Context Protocol) . But the moment an agent tries to actually complete a purchase, it hits a wall: Whose account is this order going on? What's the shipping address? How does the agent pay without a browser redirect? The standard answer is: surface a continue_url and make the human finish the job in a browser. That's not agentic commerce — that's just a fancy product search with extra steps. The real problem is identity . The agent doesn't know who it's acting for, and the store