I spent nine days selling to AI agents. Here's who actually showed up.

Sai Agarwal

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I spent nine days selling to AI agents. Here's who actually showed up.<br>A live API, every catalog, 1,835 callers, zero payments. What the agent economy actually looks like from the seller's side.

Sai Agarwal<br>Aug 12, 2026

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longwatch began as something I wanted for myself. An agent only exists while it is running — it cannot keep an eye on a page, a feed or a filing for you in between — and I kept wanting the piece that does. So I built it, and then got curious whether anybody else’s agent would pay for it.<br>Everyone building agentic payments right now is arguing from architecture. I decided to argue from logs.<br>One distinction before the numbers, because “agentic payments” is two markets sharing a name. There is consumer commerce — an agent buying you a flight, groceries, a pair of shoes. Those payments are large, occasional, and a human authorises them somewhere in the loop; the hard problems are consent, delegation, refunds and chargebacks, and that is what ACP, AP2 and the evidence-protocol work are built for. Then there is digital services — an agent paying for an API call, a data lookup, a scrape, some compute. Those payments are fractions of a cent, continuous, and no human is in the loop at any point; the hard problems are discovery, price legibility, and whether settling costs more than the thing being sold. x402 aims at the second, and everything below is about the second. I have no data on the first, and I don’t assume results in one transfer to the other.<br>In early August I put a real API behind a real paywall, listed it everywhere an autonomous agent could plausibly find it, and recorded every request for nine days. Then I removed the paywall entirely to see what changed.<br>46,287 requests. 1,835 distinct callers. Zero payments. Not “few” — zero. Not one request in nine days carried a payment.

That number is less interesting than who the 1,835 turned out to be.

What I built

longwatch is a standing-watch service for agents. You register a watch on a web page, an RSS feed, a crypto price, or a company’s SEC filings; the service polls it while you’re not running; you come back and ask what changed since your last cursor.<br>It speaks REST and MCP, and it charges over x402 — the HTTP-native payment protocol where a server answers 402 Payment Required with machine-readable payment terms and the client settles in USDC. $0.005 to create a watch, $0.001 to poll. No API key, no account, no signup. An agent with a funded wallet can discover it, pay, and use it without a human in the loop.<br>Then I did the discovery work properly. Listed on the x402 Bazaar and x402scan. Published to the official MCP registry with a DNS-verified namespace. Served /openapi.json, /llms.txt, /.well-known/x402, an A2A agent card, robots.txt, security.txt, apis.json, and an RFC 9727 API catalog. Passed @agentcash/discovery with zero warnings.<br>If an autonomous agent wanted to find and pay for a monitoring service, I made that as easy as it currently gets.

Who showed up

Traffic was healthy. Over nine days, from 1,835 distinct callers:

Then I added one line of instrumentation: MCP clients name themselves in the initialize handshake, and I hadn’t been recording it. Ninety-three distinct clients identified themselves. Here are the top ones by volume:

Read the names. Probe. Scanner. Census. Registry. Monitor. Grader. Verifier. Audit. Uptime. Crawler. Sweep.<br>Not one of the ninety-three is an agent doing work for a person. They are catalogs indexing me, monitors checking I’m alive, scanners scoring my security posture, and registries taking inventory. Several announce it in their User-Agent: mako-pulse-prober/0.1, x402-observer/1.0 (uptime+trust monitor), kkj-x402-trust-index/0.1 (liveness+consistency), forum-labs-trust-prober/1.0 (x402 endpoint quality).<br>The 1,387 payment challenges weren’t hesitant buyers. They were robots confirming my 402 was well-formed.

The control: I removed the paywall

The obvious objection is that the wallet was the friction. Fair — so I tested it. I made everything free. No payment, no wallet, no account, and I said so in every manifest, every tool description, and on the landing page.<br>Watch creations went from 0 to 10 within hours. Ten watches, from five distinct callers.<br>Every single one targeted the same company — CIK 1045810, NVIDIA — which is the example in my own documentation. And not one of the ten was ever polled.

That last part is the whole finding. longwatch only delivers value on the second visit: you register a watch, go away, come back for what changed. Ten callers registered. Zero came back. One caller created three separate watches over twelve hours without ever reading the first.<br>That is not a customer hitting a price objection. That is a robot checking that POST /watches returns 201.

How big is the market, actually

Two more measurements, both public and reproducible.<br>On-chain. x402...