Paid is on chain.Delivered is not.

curl -sL "https://vet402.com/api/v1/observatory/export.csv?days=1" | grep 90879fdb

import { createVouchClient } from "@vet402/sdk"

const vet = createVouchClient({})
const { resource } = await vet.resolve("https://api.example.com/v1/quote")
const d = await vet.getDecision(resource!.resource_id)
// pay when d.recommendation is "ALLOW" and d.degraded is false

What this is

x402 is how an agent pays an API. vet402 buys from those APIs itself and publishes whether each paid request came back with a successful answer. A 4xx or 5xx, an empty body or a 202 does not count. That shows who answers once paid. It does not check that the content is right.

What you give us

Nothing to look: no wallet, no account, no card. A free key only for score lookups and higher API limits.

What vet402 does not do

Guarantee a seller, refund, handle chargebacks, check identity (KYC), or hold your funds. A spending cap you set runs in your own process, in the SDK.

Customer count and revenue: not published. Counts on this page are read from observatory/state, export.csv and the decision document for the purchase line, at the time of the read. Methodology.

We buy. We settle. We publish the measurements.

1.The problem this memo addresses

2.Verification levels

Four levels, in order of what they cost us to run and what they prove. A result never moves up a level: an L0 probe cannot report settlement, and an L3 opinion is never folded into an L0–L2 fact.

→ 0 more columns

L0 Liveness

Does the endpoint answer correctly?

How: Probe, no purchase

Output: pass / fail / unverified

L1 Settle-through

Does the payment settle, and does a non-empty 2xx come back?

How: Real purchase

Output: n of m settled, n delivered

L2 Conformance

Does the response match the seller's own declaration?

How: Purchase + machine diff

Output: match / mismatch / no_declaration / not_checked

L3 Quality

Is the content any good?

How: Not built

Output: none: this site presents no L3 opinion

The L2 output words in that table are the ledger column l2_schema: match, mismatch, no_declaration, or not_checked. The decision document and the facts document store conform, mismatch, undeclared, or not_checked. conform is written when the re-read L2 value (l2_reading) of the latest delivery is match. mismatch is written when that re-read value is mismatch. An older mismatch row with no recorded reason is re-read first, and a cut body reads not_checked. In the other cases the decision word is not_checked when the current declaration names output (a required key or an example property), and undeclared when it does not.

3.What a verdict must carry

4.Implemented and live

Everything in this section is running right now and can be checked without asking us.

5.Status of this work

Live work is in section 4. This section is only what has not shipped, and this page will not describe it as though it had.

Progress is posted as it lands, on X @vet402_com and GitHub.

B.References

[ARXIV-2606]

98.7% of ERC-8004 reputation feedback on Ethereum has no verifiable transaction behind it. The paper reports this per chain; §1.2 quotes the Ethereum figure, which is the lowest of the three it measures. arXiv:2606.26028

[VISA-ARTEMIS-2026]

As of 2026-04-21, the Visa and Artemis PDF reports raw x402 activity of $135.7M across 178.3M transactions, and the article reports wash-and-test-adjusted totals of $15.0M across 109.6M transactions. The gap between those two published totals is 38.5% of transactions and 88.9% of volume. $135.7M and 178.3M are in the PDF. $15.0M and 109.6M are in the article and in the archived copy. The two rates are that gap, not a rate printed in either document. Visa and Artemis, Agentic Payments from the Ground Up, July 2026 (archived copy). The PDF is Agentic Payments report (PDF). The PDF states the raw totals and dates them as Artemis Analytics data as of April 21, 2026. The live article page returned HTTP 500 on earlier checks and answered HTTP 200 again when rechecked on 2026-09-29.