x402 Endpoint Check

Checks whether an x402 endpoint is alive and payable without paying it: one unpaid request, parsed 402 and a verdict (ok, suspicious or broken) with the price, wallet and network it announces, latency and reasons.

Price$0.001 USDC

Paymentx402 · Base

AccountNot needed

If it failsNot charged

Who it is for

Agents about to pay an unknown seller, directories and service hunters, and sellers monitoring their own routes.

Check an endpoint before spending on it
Monitor your x402 routes hourly
Prune dead endpoints from a catalog

How an agent buys it

POST https://a-upgradenet.com/x402/endpoint-check
Content-Type: application/json

{
  "url": "https://a-upgradenet.com/x402/web-read",
  "method": "POST",
  "body": {
    "url": "https://example.com"
  }
}

1) Answers 402 with the price (PAYMENT-REQUIRED)
2) The agent signs the payment (EIP-3009, USDC on Base) and repeats with PAYMENT-SIGNATURE
3) Receives the result + PAYMENT-RESPONSE

Example response

{
  "status": "completed",
  "url": "https://a-upgradenet.com/x402/web-read",
  "method": "POST",
  "reachable": true,
  "http_status": 402,
  "latency_ms": 412,
  "is_x402": true,
  "x402_version": 2,
  "verdict": "ok",
  "offer": {
    "network": "eip155:8453",
    "asset": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
    "amount_atomic": 5000,
    "price_usdc": 0.005,
    "pay_to": "0xbdae34e121dff6da6fbb71208322e8be0a923512",
    "scheme": "exact",
    "description": "Web Page Reader…"
  },
  "all_networks": [
    "eip155:8453"
  ],
  "content_type": "application/json",
  "issues": [],
  "checked_at": "2026-10-31T20:00:00.000Z"
}

Full documentation → See all products