The best card for an AI agent is a single-use virtual card issued for each purchase, after that purchase has been checked against limits the agent cannot change. Your everyday credit card is the riskiest choice. Prepaid and reusable virtual cards fall in between: they cap the damage, but they leave the agent holding a card it can keep using.
This page compares the options and lists what to check before you choose one. It is written for whoever has to sign off on letting an agent spend, a founder, an ops lead, or a finance owner, rather than the engineer wiring it up. For the mechanics of how a per-purchase card is issued and retrieved, virtual cards for AI agents covers it end to end.
The kinds of agent card, compared
| Card | If the number leaks | Limits the agent can't change | Approval before it pays | Works at a normal checkout |
|---|---|---|---|---|
| Your own credit or debit card | The whole card, until you cancel it | Your credit limit | No | Yes |
| Prepaid or gift card | Whatever balance is left | The balance | No | Usually; some stores refuse prepaid cards |
| Reusable virtual card from a bank or card app | Every charge until you close it, up to its limit | A limit per card | No | Yes |
| Single-use card you create by hand | One charge | Its amount | Yes, you create each one | Yes |
| Single-use card issued per approved purchase | A card issued for one approved purchase, which expires shortly after | Per purchase, per period, per merchant, across agents | Above an amount you set | Yes |
Your own card. It works everywhere, and that is the problem. An agent holding your real number holds it in its context window, its logs, and any tool traces its host keeps. A prompt injection on a web page it reads, a retry loop, or a misread price all land on your actual account, with nothing between the agent and the charge. How to give your AI agent a credit card goes through those failure modes.
Prepaid and gift cards. Loading a fixed amount caps the worst case, which is a real improvement. But inside that balance the agent can buy anything, anywhere, at any time. There is no approval step, no merchant rule, and no record of why a charge happened. Topping the card up is manual, and some merchants decline prepaid cards outright.
Reusable virtual cards. Many banks and card apps let you create a separate number with its own limit, and closing it does not affect your main card. It is better than sharing your real card. It is still reusable, so a looping agent can charge it again and again, and the limit lives in an app that knows nothing about what the agent is buying or why.
Single-use cards you create by hand. A card that dies after one charge is the right shape. The catch is the hands. If a person has to make a card for every purchase, the agent is not really buying on its own, and the person becomes the bottleneck.
Single-use cards issued per approved purchase. This is the same card shape, created automatically and only after the purchase passes your rules. The agent asks to buy something, a server it cannot reach checks the request, and a card for that one purchase exists only once the request is approved. That is the model this page recommends, and the one Authoryze is built on.
What Visa Intelligent Commerce and Mastercard Agent Pay add
Visa and Mastercard now run their own programs for payments that agents start: Visa Intelligent Commerce and Mastercard Agent Pay. Under them, the agent pays with a tokenized credential tied to a card its owner enrolled, rather than with the card itself. The merchant still sees a Visa or Mastercard card and processes it normally.
These programs are the rails, not the rules. They give the agent a credential that is not your card number. They do not decide how much your agent may spend, at which stores, or which purchases you want to see first. That layer still has to come from somewhere, and it is the layer Authoryze adds on top.
What to look for in an agent card
Whichever provider you choose, check for these.
- One card per purchase. A leaked card should be tied to one purchase, not be a standing line of credit.
- Tracked against what was approved, and short-lived. Each card should be tracked against the purchase it was issued for and expire soon after it is issued.
- Shown to the agent once. A second request for the same card should return nothing, so a retry or a leaked request ID cannot draw it again.
- Rules checked before the card exists. Limits in a system prompt are suggestions. Limits checked on a server the agent cannot reach are rules.
- Your approval above an amount you choose. Small, routine purchases go through on their own, and larger ones wait for a person.
- Limits across agents. If you run several agents, a cap per agent is not enough. You want a ceiling on all of them combined.
- Your real card stays out of it. The card the agent sees should never be the one in your wallet.
- A record of every request. What was bought, from where, for how much, which agent asked, and the reason it gave.
- Accepted where you shop. A Visa or Mastercard credential that goes into an ordinary card form works at most online stores without the store doing anything.
- Built for a team, if you are one. One funding card, rules set by admins, approvers, team-wide caps, and one monthly bill.
What to look for in AI agent payment infrastructure covers the same checklist for the platform as a whole.
How Authoryze agent cards work
Authoryze issues the last kind of card in the table. You add the card you want your agents to spend from and confirm it with a passkey. You create an agent and set its rules: an auto-approve amount, a per-transaction limit, daily, weekly, and monthly caps, and the stores it may or may not buy from. Aggregate caps across all your agents are one more setting.
When the agent wants to buy something, it sends a purchase request with the store, the amount, and its reason. If the request passes every rule and is under your auto-approve amount, it is approved right away. If it is over that amount, you get an email and approve or deny it there or in the dashboard. A request nobody decides within an hour is denied, and the agent can ask again. If you want small purchases to go through without a tap, you can also authorize an automatic spending amount for an agent, confirmed with a passkey, and your rules still apply inside it.
Once a request is approved, the agent asks for its card exactly once, when it reaches the payment step. It gets a Visa or Mastercard credential for that purchase, which Authoryze tracks against what you approved, issued against your card through Visa Intelligent Commerce or Mastercard Agent Pay, along with the billing details the store's checkout asks for. If you prefer, you can also connect your own Privacy.com account, and agents can get Privacy.com single-use Mastercard cards instead. Either way, your real card number is never in a tool response.
When a card is the wrong tool
A single-use card is built for one online purchase. It is the wrong fit for a few jobs.
- Subscriptions that rebill the same card. A card issued for one approved purchase covers that purchase, not the renewals after it, so the agent requests a new purchase when the subscription comes due.
- Paying people. Payouts, payroll, and refunds to your own customers need a payout tool, not a card.
- Crypto. Authoryze issues cards. It does not hold or send crypto.
- Cards we don't support yet. Authoryze supports Visa and Mastercard, and some issuers and countries aren't supported yet.
What it costs
On an individual account, Authoryze charges 1.5% per transaction with a $0.50 minimum, your first 5 transactions are free, and there is no subscription. The fee goes on a separate billing card that never funds a purchase. Teams pay one monthly plan instead: Team Starter is $39.99 a month for up to 100 transactions, Team Pro is $174.99 a month for up to 500, each transaction past either is $0.40, and a new team gets 20 free transactions.
Ready to give your agent a card that is not yours? Create an Authoryze account and your agent can make its first purchase in about ten minutes.