Mercury, the online bank that built its name serving startup founders, just launched a new kind of credit card. It is not for people. It is for AI agents, the automated programs that can now research, negotiate, and buy things on a company's behalf.
The idea is simple. A business gives an AI agent its own virtual card, sets a spending limit, and can see every purchase it makes. Mercury's chief executive, Immad Akhund, says founders were already handing agents human employee cards before this feature existed; the new version just adds proper controls and an audit trail on top of behavior that was happening anyway.
This matters beyond one bank. Visa, Mastercard, Google, and Stripe have each built their own systems in the past year to let AI agents make payments safely, using tokenized credentials so an agent never touches the real card number. Mastercard has already run live agent-powered payments in Hong Kong and Thailand.
Visa has opened a single integration that lets merchants accept agent payments across four different competing standards. The payment industry is not waiting to see if this trend is real. It has decided it is real and is racing to own the plumbing underneath it.
That race exists because the unsolved problem is liability, not technology. If an AI agent buys the wrong flight, overspends a budget, or gets tricked by a fake vendor, nobody has agreed whether the user, the software company, or the bank eats the loss. Every one of these new payment protocols includes an audit trail specifically because that question has no clean answer yet.
Mercury is fighting this battle while also fighting a more familiar one: keeping pace with rivals Ramp and Brex. Ramp has grown aggressively by leaning hard into AI-driven expense tools, while Brex was bought by Capital One earlier this year in a deal worth roughly five billion dollars. Mercury is reportedly raising new funding of its own at a similar valuation, and its expanded spend management tools are as much a defense against those two competitors as a bet on AI agents.
The bigger pattern here is a shrinking startup team. Fewer people are needed to run a company because software now does the work a hire used to do, which is exactly why a bank built for founders would build a product for their AI agents next.
For any business outside the startup world, this is worth watching rather than acting on immediately. Full-scale bots buying things unsupervised is not close to normal yet.
But the spend tools you already use, expense platforms, procurement software, accounting systems, are all being rebuilt with an assumption that a piece of software might eventually be the one clicking buy instead of an employee. Asking your vendors what controls exist before that day arrives costs nothing and saves a real headache later.