x402 census · machinemint-native-x402-production.up.railway.app · 38b9bf400b4e · JSON

GET /v1/base-preflight

live

Check an unsigned Base mainnet transaction before signing or broadcasting. Simulates with eth_call, estimates gas, checks sender balance and target bytecode, decodes supported token transfers and approvals, flags unlimited approvals and suspicious transaction shapes, and returns PASS, REVIEW, or FAIL. Never signs or broadcasts.

Verdict: live. The unpaid GET reached a valid 402 (confirmed by the re-probe of 2026-10-01).

Facts from the catalogs

Field Value

URL https://machinemint-native-x402-production.up.railway.app/v1/base-preflight

Method GET

Price $0.01 USDC = 10000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Network eip155:8453 (base)

payTo 0xe43e47Dd6b779fE9e591586A3e1cBA00C2f36C80

Seller machinemint-native-x402-production.up.railway.app

Catalogs cdp (row updated 2026-09-28)

Listed since (lower bound) 2026-09-28 (earliest catalog timestamp; catalogs report last-update times only)

Last catalog update 2026-09-28

CDP quality counters 2 calls and 2 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 )

Field

Value

Probe

not probed in this build

Latest re-probe

Field Value

Re-probed at 2026-10-01T14:13:42.000Z (cron)

Verdict now live changed from unprobed

HEAD / GET 200 / 402

accepts[0] {"scheme":"exact","network":"eip155:8453","amount":"10000","payTo":"0xe43e47Dd6b779fE9e591586A3e1cBA00C2f36C80","asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","maxTimeoutSeconds":300,"extra":{"name":"USD Coin","version":"2"}}

Live amount equals catalog price yes

Latency 898 ms

Error none

On-chain facts for the payTo (public address)

Field Value

Distinct payers 3

Payments 3

USDC volume $0.03

Median payment $0.01

First / last payment 2026-08-24 / 2026-09-14

Sampler-shaped share of payments 100.0%

Payers that are not samplers 0

Source forensics-2026-09-30

Address 0xe43e47Dd6b779fE9e591586A3e1cBA00C2f36C80

Declared input and output (extensions.bazaar)

{
 "input": {
  "method": "GET",
  "queryParams": {
   "data": "0x",
   "from": "0x4200000000000000000000000000000000000006",
   "to": "0x1111111111111111111111111111111111111111",
   "value": "0"
  },
  "type": "http"
 },
 "output": {
  "type": "json",
  "example": {
   "canonical_endpoint": "/v1/base-preflight",
   "chain": {
    "chain_id": 8453,
    "name": "base"
   },
   "gas": {
    "estimated": true
   },
   "reason_codes": [],
   "request_mode": "marketplace_verification_sample",
   "risks": [],
   "sender": {
    "sufficient": true
   },
   "service": "machinemint.evm.preflight",
   "simulation": {
    "ok": true
   },
   "verdict": "PASS"
  }
 }
}

Try it (unpaid: shows the 402)

curl -si -X GET 'https://machinemint-native-x402-production.up.railway.app/v1/base-preflight' -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/38b9bf400b4e/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"38b9bf400b4e"} 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 machinemint-native-x402-production.up.railway.app.