What is the Zambo x402 Day Pass?
Last updated: 2026-09-26
Zambo sells a $1.49 USDC Day Pass on Base via x402: one payment buys 24 hours of Zambo MCP access, not per-call billing. POST https://zambo.dev/api/x402/day-pass (or call the MCP tool day_pass_activate), then send X-Zambo-Key.
| Price | 1.49 USDC |
|---|---|
| Network | Base mainnet (eip155:8453) |
| Scheme | x402 v2 "exact", EIP-3009 TransferWithAuthorization |
| Window | 24 hours (86400 s) |
| Returns | access_key, expires_at, receipt_url, settlement tx |
| Gas | payer needs no ETH (relayer submits) |
| Failure | 402 refusal receipt with policy_reason |
Our own test purchase: receipt 768e9f76. Humans: buy a Day Pass by card or PayPal. How an AI agent pays for tools.
Frequently asked questions
Is the Zambo Day Pass per-call?
No. One $1.49 USDC payment on Base via x402 covers 24 hours of Zambo MCP access.
How does an AI agent buy the Zambo Day Pass?
GET or POST https://zambo.dev/api/x402/day-pass to receive the 402 challenge, sign the EIP-3009 USDC authorization, and retry the POST with the X-Payment header. Or call the MCP tool day_pass_activate. The response returns access_key and expires_at.
How does the agent use the Day Pass?
Send the header X-Zambo-Key: <access_key> on requests to https://zambo.dev/api/mcp until expires_at.
Does the paying wallet need ETH for gas?
No. The signed EIP-3009 authorization is submitted on-chain by a relayer. The wallet needs at least 1.49 USDC on Base.
Is there a receipt for the payment?
Yes. A successful payment returns a run receipt, an x402 spend receipt with an audit URL, and the settlement transaction hash. A failed payment returns a refusal receipt.