x402 census · usaref.dev · d7f1d51bdf6b · JSON

GET /v1/certified/:country/:series

live

Mexico: IVA standard rate, cited JSON with source URL, effective date and last_confirmed. GET /v1/mx/vat.

Verdict: live. The unpaid GET reached a valid 402. The live amount equals the catalog price.

Facts from the catalogs

Field Value

URL https://usaref.dev/v1/certified/:country/:series

Method GET

Price $0.10 USDC = 100000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Network eip155:8453 (base)

payTo 0x1F0409ccD20A2fb497d4DeCeF4E17e9d0688FeA6

Seller usaref.dev

Catalogs cdp (row updated 2026-10-24)

Listed since (lower bound) 2026-10-24 (earliest catalog timestamp; catalogs report last-update times only)

Last catalog update 2026-10-24

CDP quality counters 3 calls and 1 unique payers in 30 days, last call 2026-10-24 (catalog-reported, not verified on chain)

Category (keyword rule) dev-tools/utilities

Templated path yes: contains :param or {param}; probed as listed

x402Version in catalog 2

Service name / tags Usaref - N America reference · vat, mexico, reference-data, tax, gst

Unpaid probe (census of 2026-10-25)

Field Value

Probed at 2026-10-25T21:15:55.207Z

HEAD 402

GET 402

Verdict live live: valid 402 to an unpaid GET

402 carried in header+body

x402Version in the 402 2

accepts[0] {"scheme":"exact","network":"eip155:8453","amount":"100000","payTo":"0x1F0409ccD20A2fb497d4DeCeF4E17e9d0688FeA6","asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","maxTimeoutSeconds":300,"extra":{"name":"USD Coin","version":"2"}}

Live amount equals catalog price yes

Live payTo equals catalog payTo yes

extensions.bazaar in the 402 yes

PAYMENT-REQUIRED header yes

WWW-Authenticate offer Payment id="we8jkrn_BrZH-kSRKIa8AtK5e40F

Content type / server / CORS application/json / cloudflare / *

Latency 483 ms

Error Payment required

No hourly re-probe has reached this resource yet; the cron covers a rotating slice of 150 per hour.

On-chain facts for the payTo (public address)

Field Value

Distinct payers 3

Payments 40

USDC volume $0.43

Median payment $0.005

First / last payment 2026-07-22 / 2026-09-30

Sampler-shaped share of payments 100.0%

Payers that are not samplers 0

Source forensics-2026-09-30

Address 0x1F0409ccD20A2fb497d4DeCeF4E17e9d0688FeA6

Declared input and output (extensions.bazaar)

{
 "input": {
  "method": "GET",
  "queryParams": {},
  "type": "http"
 },
 "output": {
  "type": "json",
  "example": {
   "country": "MX",
   "effective_from": "2014-01-01",
   "last_confirmed": "2026-10-16",
   "series": "vat",
   "source": {
    "name": "Ley del Impuesto al Valor Agregado, Artículo 1o. (texto vigente, Orden Jurídico Nacional — Segob",
    "url": "http://www.ordenjuridico.gob.mx/Documentos/Federal/html/wo22.html"
   },
   "unit": "percent",
   "value": 16
  }
 }
}

Try it (unpaid: shows the 402)

curl -si -X GET 'https://usaref.dev/v1/certified/:country/:series' -H 'accept: application/json'

The catalog declares GET. A 402 answer carries the payment requirements in the JSON body and, for x402 v2, base64 in the PAYMENT-REQUIRED header. This page never sends a payment.

Paid checks (x402, USDC on Base)

GET https://bazaar.agentexchange.work/r/d7f1d51bdf6b/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"d7f1d51bdf6b"} places this resource at the top of the report and search pages for 30 days for $1.00, labelled. Unpaid requests answer 402 with the terms. Pricing.

Catalog references: agentic.market (CDP Bazaar front end) · this record as JSON · all resources on usaref.dev.