Why USDC is the right payment rail for AI agents

AI agents can't use credit cards. They don't have bank accounts, they can't fill out payment forms, and they definitely can't handle 3D Secure challenges. We need a payment rail built for machines.

Why not credit cards?

• Require manual form entry or stored credentials
• 3D Secure / 2FA blocks autonomous use
• Settlement takes days
• Chargebacks create risk for merchants
• Per-transaction fees eat into small purchases

Why USDC on Tempo?

USDC is a dollar-denominated stablecoin. On the Tempo network it settles in seconds with negligible fees. For agents, this means:

• Programmable — payments are just signed transactions, no forms
• Instant — settlement in seconds, not days
• Verifiable — on-chain proof of payment
• No intermediaries — agent pays merchant directly
• No chargebacks — irreversible once confirmed
• Micro-friendly — no minimum transaction size

How AgentMall uses it

When your agent calls our API:

1. We return a 402 with the payment amount (max_budget + $1.50)
2. Agent sends USDC on Tempo to our address
3. Agent retries with the transaction receipt
4. We verify on-chain and process the order

If the actual product price is lower than max_budget, we refund the difference in USDC to the payer address automatically.

If the actual total exceeds max_budget, the order fails cleanly and the full charge is refunded automatically.

Getting started with MPP

Your agent needs an MPP wallet:

$ npx agentmall onboard

Then review your wallet with tempo wallet whoami, fund it with tempo wallet fund if needed, and retry the purchase. The wallet handles the 402 challenge flow automatically, and the CLI saves a buyer token locally for later order and refund checks.

Learn more: https://mpp.dev