x402 census · api.hergertsynthora.com · d9624351020b · JSON

POST /v1/air-quality

live

SYNTHORA air-quality: live air quality for any city or lat,lon — PM2.5/PM10/ozone/NO2, EU and US AQI, and a WHO-threshold operational verdict (good/moderate/harmful). Source: open-meteo Air Quality (CAMS/ESA Copernicus), free, no key. $0.005 USDC x402 Base.

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

Facts from the catalogs

Field Value

URL https://api.hergertsynthora.com/v1/air-quality

Method POST

Price $0.01 USDC = 10000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Network eip155:8453 (base)

payTo 0xEf879BFD6C4AccB8F795136de90246e1EC245e06

Seller api.hergertsynthora.com

Catalogs cdp (row updated 2026-09-29)

Listed since (lower bound) 2026-09-29 (earliest catalog timestamp; catalogs report last-update times only)

Last catalog update 2026-09-29

CDP quality counters 8 calls and 6 unique payers in 30 days, last call 2026-09-29 (catalog-reported, not verified on chain)

Category (keyword rule) trading-signals

Templated path no

x402Version in catalog 2

Service name / tags SYNTHORA · air-quality, pm25, aqi, environment, health

Unpaid probe (census of 2026-09-30)

Field Value

Probed at 2026-09-30T23:14:32.211Z

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":"10000","payTo":"0xEf879BFD6C4AccB8F795136de90246e1EC245e06","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 none

Content type / server / CORS application/json / BaseHTTP/0.6 Python/3.12.13 / *

Latency 6,190 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 6

Payments 7

USDC volume $0.13

Median payment $0.01

First / last payment 2026-09-03 / 2026-09-30

Sampler-shaped share of payments 100.0%

Payers that are not samplers 0

Source forensics-2026-09-30

Address 0xEf879BFD6C4AccB8F795136de90246e1EC245e06 (contract: GnosisSafeL2)

Declared input and output (extensions.bazaar)

{
 "input": {
  "body": {
   "input": "Delhi"
  },
  "bodyType": "json",
  "method": "POST",
  "type": "http"
 },
 "output": {
  "type": "json",
  "example": {
   "niche": "air_quality",
   "ok": true,
   "receipt": {
    "alg": "ed25519"
   },
   "result": {}
  }
 }
}

Try it (unpaid: shows the 402)

curl -si -X POST 'https://api.hergertsynthora.com/v1/air-quality' -H 'accept: application/json' -H 'content-type: application/json' --data '{}'

The catalog declares POST. 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/d9624351020b/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"d9624351020b"} 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 api.hergertsynthora.com.