x402 census · api.onesource.io · 3f3adb5ea218 · JSON

GET /api/chain/allowance

live

ERC20 allowance via allowance (eth_call) - how much a spender is approved to move from an owner's wallet

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/allowance

Method GET

Price $0.003 USDC = 3000 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 331 calls and 329 unique payers in 30 days, last call 2026-09-28 (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 2026-09-30T23:12:43.000Z

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":"3000","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="r_cOasUYuktvPza_P2Mz5maTYlM5

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

Latency 71 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": {
  "method": "GET",
  "queryParams": {
   "contract": "0xdac17f958d2ee523a2206206994597c13d831ec7",
   "network": "ethereum",
   "owner": "0xd8da6bf26964af9d7eed9e03e53415d37aa96045",
   "spender": "0x6b175474e89094c44da98b954eedeac495271d0f"
  },
  "type": "http"
 },
 "output": {
  "type": "json",
  "example_truncated": true,
  "chars": 480
 }
}

Try it (unpaid: shows the 402)

curl -si -X GET 'https://api.onesource.io/api/chain/allowance' -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/3f3adb5ea218/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"3f3adb5ea218"} 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.