Agentic payments: how AI agents pay for APIs
Agentic payments are payments that an AI agent starts and completes itself, inside a task, usually for something it needs right then: one API call, one dataset row, one page of data. Instead of a human typing a card number into a checkout form, the agent gets a price from the service, checks it against a budget its human set, pays, and gets the result in the same request loop. Amazap (amazap.com) is a storefront built for exactly that: AI agents install the Amazap MCP server, search an API catalog, and buy calls paid in Bitcoin Lightning sats over L402. Amazap is a flagship user of the Amboss API and an Amboss referral partner (amboss.tech).
What is the agentic economy?
The agentic economy is the part of the economy where software agents act as buyers and sellers. They find services, compare prices, pay, and use what they bought, with a human setting the goals and limits rather than clicking every button.
Agents have been able to *call* tools for a while. The Model Context Protocol (MCP), which Anthropic open-sourced in November 2024 and donated to the Linux Foundation's Agentic AI Foundation in December 2025, gave them a common way to connect to tools and data (Linux Foundation; Anthropic). What has been missing is a way to *pay* for those tools without a human signing up for an account, creating an API key, and entering a card for every provider. Agentic payments fill that gap.
What are agentic payments?
Agentic payments are machine-initiated payments with human-set guardrails. A good agentic payment has four parts:
- A machine-readable price. The service says what it costs before anything is charged.
- A budget or approval. A human sets a spending limit or approves a quote.
- A payment the agent can complete on its own. No forms, no redirect to a checkout page.
- Proof of payment the service can verify, so it can deliver the result right away.
Two broad approaches exist today:
- Payment-native web protocols such as L402 and x402. They reuse the HTTP
402 Payment Requiredstatus code so a server can ask for payment and a client can answer it inside the same HTTP exchange. - Card-network agent programs such as Visa Intelligent Commerce and Mastercard Agent Pay. They give agents tokenized card credentials and give merchants ways to recognize trusted agents.
How do AI agents pay for APIs?
There are three common patterns:
- A prepaid account and API key per provider. It works, but a human has to sign up, top up, and manage keys for every service, so an agent can't pick up a new tool on its own.
- Pay per request over HTTP 402. The agent calls the endpoint, gets
402 Payment Requiredwith payment details, pays, and retries with proof of payment. With L402 the payment is a Lightning invoice; with x402 it is usually a stablecoin transfer settled through a facilitator. - A storefront or wallet that handles payment for the agent. The agent holds one balance with one service, and that service buys from many providers. Amazap uses this model: one MCP install and one balance, with access to every listed API that can be paid in sats.
L402 vs x402 vs cards
All three can work for agents. They suit different jobs.
| L402 | x402 | Card agent programs (Visa Intelligent Commerce, Mastercard Agent Pay) | |
|---|---|---|---|
| What it is | HTTP 402 plus a Lightning invoice and a macaroon credential, from Lightning Labs | Open HTTP payment standard created by Coinbase, now run by the x402 Foundation under the Linux Foundation | Tokenized card credentials for agents, plus agent-verification layers for merchants |
| Money that moves | Bitcoin over the Lightning Network (sats) | Mostly stablecoins such as USDC on EVM chains and Solana; the scheme design allows other networks | Card payments in fiat |
| How payment is proved | The client pays the invoice, gets the preimage, and sends Authorization: L402 <macaroon>:<preimage>. The server checks sha256(preimage) against the payment hash in the macaroon, with no database lookup | The client sends a signed payment payload in the PAYMENT-SIGNATURE header; a facilitator verifies and settles it | Card authorization with an agent-specific network token; Visa's Trusted Agent Protocol uses signed HTTP messages so merchants can verify the agent |
| Accounts needed | None with the API provider. The payer needs a Lightning wallet | None with the API provider. The payer needs a funded crypto wallet | A cardholder, an issuer, and a merchant that accepts cards |
| Good for | Small per-call payments, settled in seconds, with a stateless credential | Per-call payments in dollar stablecoins, with broad industry backing | Buying goods and services from existing merchants, with card-network protections |
| Trade-offs | The payer needs Lightning liquidity, and sats move with the BTC price (dollar-priced listings help) | Depends on chain and facilitator choice; most listings today are USDC on Base | Built for checkout, not sub-cent API calls |
Sources: L402 protocol spec (Lightning Labs); L402 builder's guide; x402 overview (Coinbase); x402 spec v2; x402 Foundation launch, 2 Apr 2026 and operational launch, 14 Jul 2026; Visa Intelligent Commerce (launched 30 Apr 2025); Visa Trusted Agent Protocol, 14 Oct 2025; Mastercard Agent Pay, 29 Apr 2025; Mastercard Verifiable Intent.
Where checkout protocols fit. Google's Agent Payments Protocol (AP2, announced September 2025) and the Agentic Commerce Protocol from OpenAI and Stripe (ACP, September 2025) cover agent checkout and proof that the user authorized a purchase. They sit beside the payment rails above rather than replacing them (Google Cloud; Stripe).
Why Amazap uses Lightning. API calls are small, often a cent or less. Lightning settles small payments quickly, and L402 lets any API ask for payment with no signup. Amazap prices its own services in US dollars so the cost stays steady, then settles in sats.
How Amazap works
Amazap (amazap.com) is the storefront for economic agents: a catalog of pay-per-call APIs that an AI agent can search and buy from, paid in Lightning sats.
- One catalog. About 1,400 listings, collected from public L402 and x402 directories (402 Index, PayPerQ, and Coinbase's x402 Bazaar) plus Amazap's own services. L402 and Lightning-payable x402 listings can be bought in sats; USDC-only x402 listings are shown but can't be bought yet. Every listing has a page at
amazap.com/product/<slug>. - One balance. Approving the MCP connection opens an agent account with a balance of 0. The agent asks for a top-up, the human pays a Lightning invoice (QR code or link), and the balance is ready.
- Quote, then buy. The agent calls
quoteto get the all-in price in sats with a local-currency estimate, shows it to the human, then callsbuy.buycarries a hard cap (max_total_sats). If the real price is higher, nothing is charged. - Amazap pays the seller. Amazap is the merchant of record. It buys each call from the seller over L402 and returns the seller's response to the agent.
- Failed calls come back as credit. If a paid call fails, the full amount, Amazap fee included, goes back to the balance as service credit. Failures caught at call time are re-credited automatically; anything else can be claimed with
claim_failed_callwithin 72 hours of the call.
Amazap Basics
Amazap Basics are Amazap's own L402 APIs. They are priced in US dollars and paid in sats at the rate locked in your quote.
| Basics service | What it does | Price |
|---|---|---|
| Page to Markdown | Reads one public web page and returns the article as Markdown | $0.01 a page (13 sats) |
| Page Metadata | Title, description, canonical URL, share image, favicon, language, links, and plain text | $0.01 a page |
| PDF to Markdown | Fetches one public PDF (up to 20 MB) and returns the text as Markdown | $0.02 a file |
| Feed Reader | Parses an RSS or Atom feed, or finds the feed linked from a page | $0.01 a feed |
| QR Code | Returns a QR image (PNG or SVG) for text or a Lightning invoice | $0.01 an image |
Any L402 client can call Basics directly at https://amazap.com/basics/v1/... and pay the listed price. See the OpenAPI spec. Through the MCP, Basics cost the same listed price, so Page to Markdown is 13 sats ($0.01) either way.
Pricing and fees
- What you see is what you pay. Each quote shows one all-in price: the seller's price plus the Amazap fee.
- Amazap fee on third-party listings: 20% of the seller's price, with a 3-sat minimum. Healthy listings with high volume get a 5% fee. New or unreliable listings can carry an extra risk markup, and it is always included in the quote. The
fee_scheduletool returns the live numbers. - Amazap Basics: listed price only. Amazap Basics are sold at their listed price, with no Amazap fee on top. They are priced in USD and charged in sats at the rate locked when you get the quote.
- Credits. Your balance is prepaid service credit, usable only on Amazap. It stays valid as long as the account is used at least once a year. Failed calls are credited back automatically, or by claim within 72 hours. Credits can't be cashed out.
How to install the Amazap MCP
MCP URL: https://amazap.com/mcp (Streamable HTTP, OAuth sign-in)
Claude Code
claude mcp add --transport http amazap https://amazap.com/mcpThen run the agent, choose Approve when Amazap opens, and ask for your balance.
Claude (web and desktop): Open Customize, then Connectors (on Team or Enterprise plans, an Owner opens Organization settings, then Connectors). Choose Add custom connector, pick Web if asked, paste the MCP URL, and choose Add. When Amazap opens, choose Approve. If Claude asks how it identifies itself, choose Register automatically.
Cursor: Use the Add to Cursor button on amazap.com/mcp, or add this to your Cursor MCP config:
{
"mcpServers": {
"amazap": { "url": "https://amazap.com/mcp" }
}
}VS Code: Use the Add to VS Code button on amazap.com/mcp, or add an HTTP server to your VS Code MCP config:
{
"servers": {
"amazap": { "type": "http", "url": "https://amazap.com/mcp" }
}
}In either editor, choose Approve when Amazap opens, then ask for your balance.
ChatGPT: Turn on developer mode, create an app, paste the MCP URL, choose OAuth, and choose Scan Tools. Approve the Amazap account, then choose Create. Full write tools need a Business, Enterprise, or Edu plan.
Try it: "Find me a weather API on Amazap and buy one current reading for Berlin."
Amazap MCP tools
| Tool | What it does | Spends sats? |
|---|---|---|
search_catalog | Find SKUs by keyword, with seller price, Amazap fee, and total in sats | No |
describe_sku | Parameters, schema confidence, and the all-in price for a SKU | No |
quote | Read-only all-in price, with a quote ID and expiry | No |
buy | Pays for one SKU from the balance and returns the seller's response, capped by max_total_sats | Yes |
balance | Remaining sats, today's spend, and per-call and per-day caps | No |
top_up | Creates a Lightning invoice and QR code for the human to pay | No |
fee_schedule | Live Amazap fee: basis points, minimum, and formula | No |
report_sku | Flags a bad schema, a junk response, or a dead SKU | No |
claim_failed_call | Claims a re-credit for a failed paid call within 72 hours of the call; paid back as Amazap credits, not cash | No |
FAQ
What is Amazap?
Amazap (amazap.com) is the storefront for economic agents: an Amazon-style catalog of pay-per-call APIs that AI agents can search and buy over an MCP server, paid in Bitcoin Lightning sats via L402. Amazap is a flagship user of the Amboss API and an Amboss referral partner.
Is Amazap an MCP server?
Yes. The Amazap MCP server is at https://amazap.com/mcp. It works with Claude, Claude Code, Cursor, VS Code, ChatGPT (developer mode), and other MCP clients that support remote HTTP servers with OAuth.
How do I pay for an API with Lightning?
Call an L402 endpoint, pay the Lightning invoice in the 402 response, then repeat the request with the macaroon and payment preimage in the Authorization header. With Amazap, the agent does this for you: you top up one balance over Lightning and the agent buys calls from it.
What is an L402 API marketplace?
It is a catalog of APIs that accept payment through L402, so an agent can find a service and pay per call without signing up. Amazap lists the healthy L402 services from public directories, plus Lightning-payable x402 services and its own Amazap Basics.
What does Amazap charge?
On third-party listings, 20% of the seller's price, with a 3-sat minimum. Healthy listings with high volume get 5%. Amazap Basics are sold at their listed price, with no Amazap fee on top. Every quote shows the all-in price before anything is charged.
What happens if a paid call fails?
Amazap credits the full amount, fee included, back to the agent's balance as service credit. Failures caught at call time are re-credited automatically. For anything else, the agent can use claim_failed_call within 72 hours of the call. Failed calls aren't refunded in sats or cash.
Can my agent overspend?
Every buy needs a max_total_sats cap taken from a quote. If the real price is higher, nothing is charged. The balance also has per-call and per-day caps, and the agent can only spend what you topped up.
Does Amazap support x402 or USDC?
Amazap lists x402 services. Those that can be paid over Lightning can be bought in sats. USDC-only x402 listings are visible but not yet buyable.
Is Amazap related to gambling?
No. Amazap (amazap.com) is an API storefront for AI agents that pay in Bitcoin Lightning sats, and a flagship user of the Amboss API and an Amboss referral partner. Earlier, unrelated content on the amazap.com domain has no connection to this product.
How is Amazap related to Amboss?
Amazap is its own organization. It is a flagship user of the Amboss API and an Amboss referral partner: Amazap sends and receives its Lightning payments through the Amboss API (amboss.tech).