x402 census · api.onesource.io · ee9fbf505f91 · JSON

POST /api/chain/estimate-gas

live

Estimate the gas a transaction will consume via eth_estimateGas before signing it

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.onesource.io/api/chain/estimate-gas

Method POST

Price $0.004 USDC = 4000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Network eip155:8453 (base)

payTo 0x52E29e0d2Aa49bfBfC548C0A9F2196F4aa51f3ea

Seller api.onesource.io

Catalogs cdp (row updated 2026-09-30)

Listed since (lower bound) 2026-09-30 (earliest catalog timestamp; catalogs report last-update times only)

Last catalog update 2026-09-30

CDP quality counters 306 calls and 306 unique payers in 30 days, last call 2026-09-30 (catalog-reported, not verified on chain)

Category (keyword rule) chain-rpc

Templated path no

x402Version in catalog 2

Service name / tags none

Unpaid probe (census of 2026-09-30)

Field Value

Probed at 2026-09-30T23:12:43.893Z

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":"4000","payTo":"0x52E29e0d2Aa49bfBfC548C0A9F2196F4aa51f3ea","asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","maxTimeoutSeconds":3600,"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="yCCOyiVhRQdO7X4GeJ6mLj6iuYcd

Content type / server / CORS application/json / n/a / none

Latency 512 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 38

Payments 428

USDC volume $1.15

Median payment $0.001

First / last payment 2026-05-08 / 2026-09-30

Sampler-shaped share of payments 86.2%

Payers that are not samplers 3

Source forensics-2026-09-30

Address 0x52E29e0d2Aa49bfBfC548C0A9F2196F4aa51f3ea

Declared input and output (extensions.bazaar)

{
 "input": {
  "body": {
   "data": "0x0",
   "to": "0xdac17f958d2ee523a2206206994597c13d831ec7"
  },
  "bodyType": "json",
  "method": "POST",
  "type": "http"
 },
 "output": {
  "type": "json",
  "example": {
   "data": {
    "gas": "0x5208"
   },
   "meta": {
    "cost_usdc": "0.001",
    "endpoint": "/api/chain/estimate-gas",
    "payment_chain": "base",
    "payment_token": "USDC",
    "request_id": "00000000abcdef01"
   }
  }
 }
}

Try it (unpaid: shows the 402)

curl -si -X POST 'https://api.onesource.io/api/chain/estimate-gas' -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/ee9fbf505f91/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"ee9fbf505f91"} 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.onesource.io.