Zambo receipt guide

How Do I Let My AI Agent Buy API Access Itself?

Plain answers about using Zambo, keeping your work, and checking receipts. A receipt shows what Zambo recorded for one call. It does not prove the answer is right.

Last updated: 2026-10-03

By Brennan Zambo

In short

The agent requests an Zambo link, receives HTTP 402 with payment terms, pays, and retries with proof. The Zambo agent Day Pass costs $0.99 USDC on Base for 24 hours. This flow needs no account and no API key.

The request, payment, and retry

The generic sequence is short: the agent calls an Zambo link, receives HTTP 402, pays the requested amount, and retries with proof. The Zambo agent Day Pass is $0.99 USDC on Base for 24 hours. The live Day Pass Zambo link returns HTTP 402 until the agent pays.

No account or API key

This agent flow does not require a Zambo account or API key. The payment challenge is returned by the Zambo link, and the agent uses the challenge to complete payment before retrying. Keep the payment proof separate from the receipt for any later tool call.

Payment evidence is not execution evidence

The payment flow documents access. A tool call has its own result and can return a verifiable receipt. A payment alone does not prove that a later call succeeded. For the related crypto payment question, see which endpoints can accept crypto payments from agents.

Frequently asked questions

How Do I Let My AI Agent Buy API Access Itself?

Point the agent at a payment-enabled endpoint. It receives HTTP 402 with payment terms, pays $0.99 USDC on Base for the 24-hour agent Day Pass, then retries with proof. No account or API key is required for this flow.

What does the first HTTP 402 response mean?

It is the payment challenge. The endpoint returns the requirements before access is granted; the agent pays and retries the request with proof.

How long does the agent Day Pass last?

The agent Day Pass is $0.99 USDC on Base for 24 hours.

Next step

A first request returns HTTP 402 with the payment challenge. Open the agent Day Pass Zambo link

For developers and agents

Zambo gives AI work a receipt you can check. For people: add Zambo to your AI app and ask for a job. These technical links are for developers and AI agents. One hosted MCP at https://zambo.dev/mcp. Check the proof for recorded tool calls (verify a receipt). Agents: 24-hour Day Pass, $0.99 USDC on Base via x402, not per call. People: Zambo Pass $29/mo or $290/yr; holder pass $19/mo for verified $ZAMBO holders.

Start here: For AI agents · Add Zambo · Check a receipt · Answers · Guides · What a receipt is · Open receipt format (draft) · All tools · Pricing · Day Pass: $0.99 · Agent Day Pass · Switch AIs without losing your work · Connect your AI · Founder · Source code
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