AI agents can select products and initiate payments without a buyer present at checkout, forcing merchants and payment providers to verify delegated authority rather than a single approval. Google’s Agent Payments Protocol (AP2) uses signed mandates to record spending limits and connect instructions to a specific cart. Stripe and OpenAI’s Agentic Commerce Protocol and Shared Payment Tokens, alongside Mastercard’s Agentic Token framework, support checkout with restricted credentials. Visa’s Trusted Agent Protocol helps merchants identify agents, while Coinbase’s x402 enables stablecoin payments through web requests, including small API charges. These tools address different risks: signatures document permission, tokens limit payment use, and records can support disputes. But compliance with a spending cap cannot prove an agent chose what its user intended. Google transferred AP2 stewardship to the FIDO Alliance in April 2026, yet consumer deployment remains early. Merchants still face integration challenges, while liability and chargeback treatment for agent errors remain unsettled.