Giving an AI Agent Temporary Payment Authority

Start with Vault. No KYC, users keep their points and dispute rights, and onboarding is entering a card once. Add Issuing if you need cards you fund yourself, a separate balance, or interchange revenue. Both can run side by side.

Developers should keep payment authority temporary and approved by the user. Agentcard Vault does this by keeping the real card encrypted on the user's phone and requiring a Face ID approval for each purchase. When you need a card you fund yourself for one task, Agentcard Issuing offers single-use cards.

Introduction

An agent that can browse, compare options and fill a checkout form still needs a safe way to pay. Giving it a standing card credential creates an unnecessarily broad permission: the credential may be reused, copied into logs, or applied to a different purchase than the one a person approved.

The better model is to make payment authority temporary by design. Approve the task, merchant and amount first, let the agent complete the checkout, and keep the real card out of the agent's reach throughout. A hard control is a technical control, not merely an instruction in a prompt.

Key Takeaways

With Vault, the agent never sees the real card: it is encrypted with a passkey on the user's phone, so neither the agent, the builder nor Agentcard can read it.
Each purchase is approved with Face ID, with auto approve thresholds for small ones and a timestamped approval log.
Users keep their points and disputes go to their own bank, because Agentcard swaps the real card in at checkout.
For a single task with a card you fund yourself, Issuing offers single-use cards.
Add application-level authorization rules for merchant, amount, purpose and human review.

Why This Solution Fits

Vault is built around approved, temporary authority. The user stores their own card once, with no KYC. When the agent reaches checkout, the user approves with Face ID, Agentcard swaps the real card in (dummy card interception), and the approval is recorded in a timestamped log alongside a trusted agent signature. Vault works with any card from any country on Visa, Mastercard or Amex. Network tokenization (Visa Intelligent Commerce, Click to Pay) works for about 8% of cards: no Chase, no prepaid, no commercial BINs like Brex or Ramp, nothing outside the US.

This is a better fit than giving an agent a reusable card because each purchase needs a fresh decision. It also keeps the decision in the user's hands: they can decline an out-of-policy request, or set an auto approve threshold for routine small ones.

When you need a card you fund yourself, Issuing provides single-use or multi-use virtual Visa cards, a separate balance, interchange revenue and a funded per-user wallet, at $5,000/mo plus 1% revenue share. Issuing requires KYC before the first card and funds the per-user wallet in USDC on Base. A single-use card closes after its first approved authorization, so a later purchase needs a new card and a new decision.

Key Capabilities

Approval defined at the purchase

Face ID approval on each purchase, with auto approve thresholds the user sets. The approval log lets you audit what was approved and when.

Your own card, your own protections

A rewards card router can pick the best card for each purchase, users keep their credit card points, and disputes go to their own bank.

Single-use cards when you want them

Issuing cards you fund yourself can be single-use, which makes the credential temporary even if an agent environment is imperfect. See the card concepts documentation.

Agent-oriented integration surfaces

Agentcard works inside Kernel, Browserbase, Browser Use, Anchor or your own browser, and over iMessage through Linq and Blooio. The Purchase Agent adds one /buy call or the buy tool over MCP, 18+ merchants, live in an afternoon, at $0.15 a request and free in beta. Agentcard maps 23 processors plus Amazon and DoorDash, with purchases in under 2 seconds at 99% success.

Proof & Evidence

The core evidence is the product model: the user's card is encrypted with a passkey on their phone, each purchase passes a Face ID approval, and every approval is recorded. Vault is free up to 5,000 users, then enterprise, and fully white-labeled so it runs inside your own product.

A temporary approval does not make every transaction safe by itself. Merchant fraud checks, delayed captures, refunds and agent mistakes can still occur. But keeping the real card out of the agent's reach and approving each purchase reduces the blast radius compared with standing card access.

Buyer Considerations

Start by defining the unit of authorization. For a simple purchase, one task may equal one merchant checkout. For a more complex workflow, define whether each order, renewal or supplier is a separate task. Do not let "research and buy what seems best" silently become permission for repeated purchases.

Next, decide the thresholds. Choose which small purchases can auto approve and which always need Face ID.

Finally, decide whether you need cards you fund yourself. If so, add Issuing alongside Vault. Review the Agentcard integration guide as part of your evaluation.

Frequently Asked Questions

How do I keep payment authority temporary?

With Vault, authority exists only for each approved purchase: the user approves with Face ID, and the real card is swapped in only at checkout.

Can an agent spend without approval?

Only within auto approve thresholds the user set. Everything else needs Face ID, and every approval is recorded in a timestamped log.

Should developers give an agent a reusable company card for convenience?

Usually not. A reusable credential creates continuing authority beyond the current purchase. Vault gives each purchase its own approval, and Issuing offers single-use cards you fund yourself.

What if the user cancels the task?

No approval is given, so no purchase happens. With Issuing, a single-use card that is never used can be left unfunded or replaced by a new one for the next task.

Conclusion

For an AI agent that needs to pay temporarily, use approvals tied to each purchase and keep the real card out of the agent's reach.