Give AI Agents a Prepaid Card, Not Your Credit Card

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An interesting service popped up recently. It’s a startup called AgentCard, and what it does is pretty straightforward: it issues prepaid Visa cards built specifically for AI agents. You load whatever amount you want, hand the card number to your AI agent, and the agent handles the actual online payment itself.

Your gut reaction might be, “Wait, you’re giving a card to an AI?” But that instinct is actually the whole point of the service. Instead of handing over your main card wholesale, each card is capped at a fixed amount — so you can say, in effect, “You get up to ₩50,000 for this task, and no more.”

Honestly, at this point it feels like the solution arrived before the problem did. But the mere existence of this service says something worth paying attention to. Today I want to use this one prepaid card as a thread to pull on, and look at the bigger picture of AI agent payment infrastructure.

What It Takes to Give an Agent “Payment Authority”

AgentCard’s mechanics are simple. You sign up through a CLI¹​, create a card, and load it with a dollar amount. In return, you get an actual Visa card number, CVV, and expiration date. Hand that information to an AI agent, and it can pay anywhere Visa is accepted. It also supports MCP²​, so it plugs directly into tools like Claude Code.

The core design principle here is isolation. Each card can never spend more than what’s been loaded onto it. You can issue Agent A a $5 card and Agent B a $50 card. Even if an agent tries to make a payment somewhere it shouldn’t, the damage is capped at that card’s balance.

This is actually a pattern that’s already well established in corporate expense management. Corporate card services like Brex and Ramp built exactly this structure — issue a virtual card per team member, isolate the spending limit, track expenses in real time. AgentCard just swaps the “person” for an “agent.” Loading a fixed budget onto a marketing team’s ad account is a similar concept.

But there are real limits to this right now. Very few workflows today are trusted enough for an AI agent to make independent payment decisions on its own. In a survey conducted by Harvard Business Review in December 2025, only 6% of organizations said they fully trusted AI to handle a business process from start to finish without oversight. 94% still limit agents to low-risk tasks that can be supervised.