Mastercard opened early access to Agent Pay for Machines this week. In the demo, an AI agent planning a sample ad campaign made 9 payments to 2 merchants on one approved budget. No separate accounts, API keys, or invoices. It runs on x402, with Coinbase wallets and settlement on Base. The line from their post that stuck with me: "Payments aren't the hard part. Authority is." That matches what I heard at Money20/20 this week. Nobody was arguing about rails. They were arguing about who gets to say yes: KYC, spend limits, and who's liable when an agent pays the wrong party. It's still a pilot, not a commercial product. But it's the clearest picture yet of how a card network wants this to work.