I pay for these APIs with my own wallet and publish what happened. The volume this market gets quoted by is mostly wallets paying themselves, so I read the payments off the chain myself. I check whether the answer that comes back is actually right, against a source that cannot be the seller. And the verdict an agent gates on is backed by money that moved. Every weight and threshold behind that is published at how we grade. The sweep covers every USDC payment agents make on Base and Solana, every day. Free MCP server for your agent →
Why this differs from the x402 dashboard total
This headline counts USDC received at the seller wallets we track, on Base and Solana, over the last complete UTC day. Of it, $34,324 settled on Base and $74,048 on Solana (Solana is mostly Bitrefill and Laso). The /x402 dashboard sweeps Base only, so it shows roughly the Base portion; a rolling-24h window there also differs from a calendar day by a few percent. Every figure on this site carries its scope for exactly this reason.
Preflight is the one call an agent makes before it pays an unfamiliar x402 API, the check it runs before it hits the 402. It collapses everything measured here, live price and payment-address honesty, phantom paywalls, and the delivery receipts, into a single verdict it can gate on: CLEAR nothing alarming, HOLD pay but verify, ABORT do not pay without checking, UNRATED no data yet. How each verdict is decided.
1820 clear · 111 hold · 54 abort · 656 unrated, across 2641 x402 sellers. 152 of them advertise a category you can get free upstream (an exchange price, weather, a chain read, a web search), and each verdict says so. Machine-readable at /api/preflight.json, or have an agent call the preflight MCP tool. The contract is at /preflight/spec. Whatever it says, always read the payTo and the amount from the live 402 and sign against those, never a listing.
Every verdict also says how much it is backed by, because a green a real wallet has tested is not the same evidence as one we only glanced at. verified = a payment settled and the result was gradeable · probe only = the free live checks measured its listing · unproven = listed, or nothing measurable yet. Of 1820 CLEAR verdicts, only 570 are verified by real payment; the rest are clean on the free probe but unpaid, which says the seller’s live 402 looks honest, not that anyone has spent against it. This is the difference between this and a probe-only safety check, made explicit on every verdict.
Abort (54)
A live payment address that disagrees with the listing, a phantom paywall, or a paid call that returned none of its promised goods. Check the live 402 before paying any of these.
Its live payment address does not match its listing. Money would go to an address the directory does not name.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
ABORTprobe onlyaegis-ai.xyz0 receipts · score 35
Its live payment address does not match its listing. Money would go to an address the directory does not name.
Its live quote disagrees with its listing. Budget from the live 402, never from the listing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Paid in full and returned none of its 4 promised fields, confirmed on two calls.
This looks like crypto price data, which is available free from Coinbase or the chain, free. A paid call buys packaging or convenience, not exclusive data, so confirm you need it before paying.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Its live payment address does not match its listing. Money would go to an address the directory does not name.
This looks like gas price data, which is available free from the chain's own base fee, a free read. A paid call buys packaging or convenience, not exclusive data, so confirm you need it before paying.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
ABORTprobe onlyconc-exe.xyz0 receipts · score 55
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
This looks like WHOIS data, which is available free from public WHOIS, free. A paid call buys packaging or convenience, not exclusive data, so confirm you need it before paying.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Paid in full and returned none of its 2 promised fields, confirmed on two calls.
ABORTprobe onlyscopeapi.dev0 receipts · score 55
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Its live payment address does not match its listing. Money would go to an address the directory does not name.
This looks like chain data data, which is available free from any public RPC, free. A paid call buys packaging or convenience, not exclusive data, so confirm you need it before paying.
Almost all its revenue comes from a single wallet, so volume is not broad demand.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
This looks like weather data, which is available free from NWS and Open-Meteo, both free. A paid call buys packaging or convenience, not exclusive data, so confirm you need it before paying.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Its live payment address does not match its listing. Money would go to an address the directory does not name.
This looks like gas price data, which is available free from the chain's own base fee, a free read. A paid call buys packaging or convenience, not exclusive data, so confirm you need it before paying.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
Not yet bought from, so delivery is unverified. Absence of a grade is not a bad grade.
Phantom paywall: it returns a priced 402 for routes that cannot exist, which means its payment middleware runs before route validation. A quote is not evidence of a real endpoint, and a paid call to a wrong route may settle and return nothing.
1820 sellers show nothing alarming: their live price and payTo match their listing and no paid call has come up short. Each carries its own verdict at /api/preflight.json and a badge on its service page. A clear preflight is a payment-safety verdict, not a promise the goods are worth buying.