Last week a marketplace opened with over 60 services designed to be consumed not by humans but by AI agents.
Among them:
- Full-text search across every SEC filing ever made, charged per query
- CAPTCHA solving for agents who hit verification walls designed for bots
- Physical letters printed and mailed from a document and an address
- Image generation from fal.ai across over 600 AI models at fractions of a cent per request
The protocol powering this marketplace is the Machine Payments Protocol (MPP), from Stripe and Tempo, which lets agents pay using cards, stablecoins, or Lightning in a single HTTP request. In its first week, 894 agents executed over 31,000 transactions across the directory at prices ranging from $0.003 to $35 per request.
None of these services have a checkout page. Their catalogs are machine-readable schemas. Pricing is embedded in their HTTP responses. Agents read schemas, send requests, pay, and receive outputs in a single exchange.
A merchant used to be a storefront. Even as commerce moved online, the pattern stayed the same: product images, a checkout page, a confirmation email. In e-commerce, “headless” meant decoupling the frontend from the backend. In the new agentic economy, headless means eliminating the frontend entirely.
This is the headless merchant: a business with no storefront, no accounts, and no sales team. Just a server, a set of endpoints, and a price per call.
The payment rails that make this possible are now live. x402 and MPP each take a different approach, but both embed payments directly into HTTP requests. Visa’s CLI tool extends card rails to the terminal. These are the primitives that power headless merchants.
Why headless merchants are different
Stand up a traditional software business and you need a website, a checkout flow, user accounts, customer service, subscription management, a billing system, and a sales team or marketing budget to acquire customers. A headless merchant needs a good API and a thin layer of middleware. That is the business.
This matters because of who the buyer is. An agent arrives with a task, a budget, and constraints. It evaluates the endpoint’s documentation, pricing, and reliability. If the service meets the criteria, it pays and moves on.
The payment is the authentication.
Simon Taylor (@sytaylor) calls this the “intention economy“: the agent arrives with intent already formed, and the merchant’s only job is to fulfill it.
This inverts how you think about building a business. The agent buyer will never see your website. It will see your API docs, your pricing, and your uptime. A headless merchant with clean docs and predictable pricing will almost always beat one with a beautiful website and a mediocre API.
Commerce used to happen in places: a store, a website, an app. Headless merchants move commerce to moments. The instant an agent needs a capability it doesn’t have, it transacts.
The model shift
Subscriptions amortize the cost of billing. Signing up, entering a card, choosing a tier, managing a renewal: all of that overhead exists because charging a human three-tenths of a cent for a single API call wasn’t practical. Agents can handle it. An agent can pay fractions of a cent per request, thousands of times a day, across dozens of services, without ever creating an account.
This changes which businesses are viable. A service that charges $0.003 per image generation or $0.01 per web scrape doesn’t need a sales team. It doesn’t need a free tier or worry about churn, because there is no subscription to cancel and no relationship to manage. It just needs to be good enough that when an agent evaluates its documentation and pricing, it gets chosen.
If you sell a service behind an API key and a subscription today, there is a version of that product that charges per request, requires no account, and is discoverable by any agent with a wallet. That version may reach customers your subscription product can’t, because the customer never would have signed up. The agent would have just moved on to the next endpoint.
Pay-as-you-go may replace the subscription for a growing class of services. Not because subscriptions are bad, but because the buyer no longer needs them.
The merchants are the story
Earlier this month I argued that the next wave of commerce would be built by merchants choosing stablecoins over nothing, because traditional processors couldn’t underwrite them. Since then, the infrastructure has moved faster than expected. Card networks are extending their rails to agents. New protocols have emerged that support cards, stablecoins, and settlement models like per-session billing. The rails are no longer the bottleneck.
What matters now is the merchants. A headless merchant with a clean API, reliable output, and per-request pricing is a new kind of business, one with a cost structure that couldn’t have existed five years ago and a buyer base that didn’t exist a year ago.
The biggest opportunity in agentic commerce isn’t building the next payment rail. It’s building the headless merchants those rails were designed to serve. The next generation of merchants won’t have storefronts. They’ll have endpoints.
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