Do AI agents actually pay for APIs?
We run pay-per-call x402 APIs on two data sites. In 45 days they sent 132,016 payment challenges and received 42 payments. Almost every payment came from a bot checking that payment works.
No, not yet. Not ours, anyway. We run pay-per-call APIs on two data sites, the Vault Report (precious metals) and Mining Incidents (MSHA mine safety). Both speak x402: a request without payment gets an HTTP 402 with a price, and a client that wants the data pays in USDC on Base and asks again. Prices are one or two cents.
Over 45 days, from September 10 to October 24, 2026, the two sites answered 184,303 API requests. They sent 132,016 payment challenges. They got paid 42 times, for $0.47 in total.
That is one payment per 3,143 challenges. The more interesting question is who the 42 were.
Who paid
38 of the 42 payments came from bots that announce what they are. Their user agents point to sites like vet402.com/observatory, probe402.com/method and settled.tools/bot, and several say it outright: "paid delivery probe", "pays once, records delivery", "x402 audit". These are directories and scorecards. They pay a cent to check that a seller's 402 is honest and that the data arrives after payment, then publish the result.
The remaining 4 payments came from two wallets whose client said only "node". Each wallet paid the Vault Report's COMEX deliveries endpoint and Mining Incidents' fatalities endpoint once, on the same day (September 12 for one, September 17 for the other), and never came back. That pattern looks like someone trying x402 against a list of sellers, not a customer with a job to do.
Thirteen wallets paid in all, and nine of them paid both sites. A buyer who needs gold premiums rarely also needs mine fatality data. A tester working through a seller list hits both.
Where the 132,016 challenges went
Most of the traffic that gets a 402 is not trying to buy anything either. 79% of all requests came from clients that call themselves uptime monitors, crawlers or indexers, or were HEAD checks that never ask for data. They see the price and leave, which is what they are built to do.
| Client | 402 challenges | Payments |
|---|---|---|
| User agent names Claude or ChatGPT | 19 | 0 |
| Generic HTTP libraries on the Vault Report (axios, python-httpx, Go, undici, python-requests, curl) | 1,936 | 0 |
The 19 challenges to clients that named an AI assistant are the closest thing to the agent everyone pictures: a model, mid-task, hitting a paid endpoint. All 19 stopped at the 402.
The 1,936 generic-library challenges are scripts and agents that do not say who they are. Any of them could have paid. None did.
Why, as best we can tell
The buyers are not here yet. The people building on x402 right now are mostly building for sellers and for each other: facilitators, directories, trust scores, delivery checks. That work comes first for a reason. An agent that pays strangers needs some way to know which strangers deliver, and these bots are making that list. Our two sites are on it because a tester paid a cent and got the data.
What is missing is the other side: assistants that hold a wallet and are allowed to spend from it without a human approving each call. Every AI client that reached us stopped at the 402.
So the honest answer to "do AI agents pay for APIs?" is: the agents that pay today are mostly paying to test whether paying works. We will rerun these numbers as wallets show up in mainstream assistants. That is the change that would move them.
How we counted
We counted USDC transfers into our three x402 receiving wallets on Base (Vault Report, Mining Incidents, and a ByShovel wallet that received nothing) from block logs, not from our own request logs, because a request log's "paid" flag is not settlement. We left out our own seed wallet; it made no payments in this window. Every on-chain payment matched a paid row in the site's request log, 29 for 29 on the Vault Report and 13 for 13 on Mining Incidents, which is how each payment got its user agent. The window is 45 days because the public Base node we read from keeps about 47 days of logs.