The x402 Observatory
Abstract
Every endpoint in the public x402 discovery catalog, observed daily: is it still listed, and does its payment wall answer a valid 402 challenge when approached with the method it declares. This table is L0: no purchase is attached; the challenge itself is the observable. L1 settle-through purchases, when made, are on each endpoint's page — they are not mixed into these cells. pass / fail / unverified are defined measurements, not opinions — definitions here. unverified is not a failure: it means the catalog entry does not declare enough for a machine to check. No account. To verify a payee before you pay, verify a payee; a key is only for the score API. Headline numbers: State of x402.
1.Observed endpoints
17,167 endpoints on record, ordered by observed call volume (catalog-reported, last 30 days). Page 96 of 430.
| Endpoint | Network | Declared method | Catalog | L0 | Last probed | Calls 30d |
|---|---|---|---|---|---|---|
| poketpoker.com/api/hands/AhKh | eip155:8453 | GET | active | unverified | — | 3 |
| polymarket-signal-api.pwnker-polymarket-signals.workers.d… | eip155:8453 | GET | active | unverified | 2026-08-14 08:53 UTC | 3 |
| polynews.news/api/v1/feed | eip155:8453 | GET | active | pass | 2026-08-16 10:39 UTC | 3 |
| port-scanner.underscoredone.com/scan | eip155:8453 | POST | active | unverified | 2026-08-14 08:52 UTC | 3 |
| postcode-api-production.up.railway.app/lookup/postcode | eip155:8453 | POST | active | unverified | — | 3 |
| pro-api.coingecko.com/api/v3/x402/onchain/simple/networks… | eip155:8453 | GET | active | unverified | 2026-08-14 08:52 UTC |
2.Reading this table
Catalog is presence in the public discovery catalog: active means listed as of the latest snapshot; delisted means the entry was present on an earlier day and absent on a complete fetch — with the before/after recorded on the endpoint's page. L0 is the payment-wall measurement: pass — a probe using the declared method received HTTP 402 with a parseable accepts array consistent with the catalog declaration; fail — two or more consecutive probes contradicted that (each with a recorded reason); unverified — not enough declared to measure, or the evidence threshold is not yet met. A day on which our own fetch was incomplete produces no delisting judgements at all.