Visa's July 2 announcement wasn't a pilot. AI agents completed purchases with independent European merchants, authenticated by Payment Passkeys, recognized through a Trusted Agent Protocol and Agent Directory. Over 30 issuers. Four merchants spanning travel, retail, and e-commerce. Live transactions, not controlled demos.
So the infrastructure for making agent purchases is arriving faster than the infrastructure for contesting them.
Today's chargeback process asks a binary question: did the cardholder authorize this transaction? Agentic commerce produces a harder case. The account was valid. The spending limit held. The merchant processed correctly. But the agent booked the wrong flight, interpreting "under $500 at travel merchants" in a way the user didn't intend. Both ends of the transaction look right, and something in the middle went wrong.
Resolving that requires evidence the dispute system doesn't yet collect: what the user actually asked for, how the agent interpreted the constraints, why it chose this option over that one. Visa's rules already require "cardholder-defined payment instructions" and 120-day order confirmation retention. Those preserve what was processed. They don't preserve the reasoning that got there. No public agent-specific dispute code exists in either major network's current guides.
Lastminute.com's CEO called it "early days." He's right, and the specifics of what comes next matter enormously. The mandate, the constraint interpretation, the decision trace: these are where contestability stops being an abstract design principle and starts costing someone real money.
What's live: 30+ European issuers (including Barclays, BBVA, ING, Revolut, Klarna, Lloyds) transacting with lastminute.com, Frasers, Cleverbridge, and BrickDepot
Authentication: Visa Payment Passkeys meeting EU Strong Customer Authentication requirements
Agent identity: Trusted Agent Protocol + Agent Directory give merchants a consistent signal to distinguish verified AI agents from unverified traffic
User controls (via OpenAI partnership): Spending limits, merchant categories, required approvals, tokenized credentials, real-time fraud monitoring
What Visa's rules require: Defined payment instructions, identity verification, cardholder responsibility acknowledgment, 120-day order confirmation retention
What's missing from public dispute guides:
- No agent-specific reason code (Visa or Mastercard)
- No mandate-content field in dispute files
- No constraint-interpretation evidence category
- No decision-trace representment standard
The liability clause to watch: Visa's rules state the cardholder is responsible for agent actions "as if the cardholder initiated the transaction," while simultaneously requiring defined instructions and controls