Agent Exchange x402 census and directory

x402 census · riddlex402.vercel.app · f9aa68845933 · JSON

GET /api/riddle

live

Pay a micro-fee in USDC on Base mainnet to receive a riddle and its answer.

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

Facts from the catalogs

FieldValue
URLhttps://riddlex402.vercel.app/api/riddle
MethodGET
Price$0.002 USDC = 2000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Networkeip155:8453 (base)
payTo0x255CdB4e42afeFc7120B0388eB78f96d996d387b
Sellerriddlex402.vercel.app
Catalogscdp (row updated 2026-09-26)
Listed since (lower bound)2026-09-26 (earliest catalog timestamp; catalogs report last-update times only)
Last catalog update2026-09-26
CDP quality counters72 calls and 47 unique payers in 30 days, last call 2026-09-26 (catalog-reported, not verified on chain)
Category (keyword rule)other/unknown
Templated pathno
x402Version in catalog2
Service name / tagsRiddle Oracle · riddle, puzzle, fun, text

Unpaid probe (census of 2026-09-30)

FieldValue
Probed at2026-09-30T23:12:12.151Z
HEAD402
GET402
Verdictlive live: valid 402 to an unpaid GET
402 carried inheader
x402Version in the 4022
accepts[0]{"scheme":"exact","network":"eip155:8453","amount":"2000","payTo":"0x255CdB4e42afeFc7120B0388eB78f96d996d387b","asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","maxTimeoutSeconds":300,"extra":{"name":"USD Coin","version":"2"}}
Live amount equals catalog priceyes
Live payTo equals catalog payToyes
extensions.bazaar in the 402yes
PAYMENT-REQUIRED headeryes
WWW-Authenticate offernone
Content type / server / CORSapplication/json / Vercel / none
Latency5,509 ms
ErrorPayment 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)

FieldValue
Distinct payers19
Payments111
USDC volume$0.22
Median payment$0.002
First / last payment2026-07-13 / 2026-09-22
Sampler-shaped share of payments100.0%
Payers that are not samplers0
Sourceforensics-2026-09-30
Address0x255CdB4e42afeFc7120B0388eB78f96d996d387b

Declared input and output (extensions.bazaar)

{
 "input": {
  "method": "GET",
  "pathParams": {},
  "queryParams": {},
  "type": "http"
 },
 "output": {
  "type": "json",
  "example": {
   "answer": "An echo",
   "name": "Riddle of the moment",
   "riddle": "I speak without a mouth and hear without ears. What am I?"
  }
 }
}

Try it (unpaid: shows the 402)

curl -si -X GET 'https://riddlex402.vercel.app/api/riddle' -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/f9aa68845933/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"f9aa68845933"} 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 riddlex402.vercel.app.