x402 conformance verification for wallet developers. Pay $1.00 USDC on Base or S...
https://underground.substratesymposium.com/api/merchant-keyOverview
x402 conformance verification for wallet developers. Pay $1.00 USDC on Base or Solana; receive an Ed25519-signed attestation that your client completed a real 402→auth→settle→deliver cycle on production infrastructure. Includes @maraventano/map decoder source (src/read.js) inline for URL parsing in future transactions. Use in CI pipelines, before SDK releases, or as agent-to-agent trust anchor.
Protocol
x402
Price
$1.00
Payment Asset
USD Coin
Payment Network
eip155:8453
Category
crypto/transactions
Provider
underground
Source
bazaar
Indexed
2026-07-18 19:08:58
Health
Status
healthy
Latency (p50)
493ms
Uptime (30d)
100.0%
Reliability Score
95/100
Last Checked
2026-10-31 07:15:29
Last Healthy
2026-10-31 07:15:29
Consecutive Failures
0
x402 Payment Validation
Payment Requirements
Valid
Asset Verified
—
Facilitator
—
Input Schema
{
"method": "GET",
"queryParams": {},
"type": "http"
}
Output Schema
{
"example": {
"content": "Signed Ed25519 attestation of end-to-end x402 conformance plus @maraventano/map decoder source inline",
"delivered_at": "2026-07-18T17:00:00Z",
"product": "certify_your_wallet",
"title": "Certify Your Wallet + MerchantKey"
},
"type": "json"
}
Recent Health Checks
| Time | Status | HTTP | Latency | Error |
|---|---|---|---|---|
| 2026-10-31 07:15:29 | healthy | 402 | 510ms | |
| 2026-10-31 06:12:37 | healthy | 402 | 468ms | |
| 2026-10-31 05:15:15 | healthy | 402 | 469ms | |
| 2026-10-31 04:11:32 | healthy | 402 | 489ms | |
| 2026-10-31 03:23:15 | healthy | 402 | 486ms | |
| 2026-10-31 02:14:33 | healthy | 402 | 501ms | |
| 2026-10-31 01:14:48 | healthy | 402 | 546ms | |
| 2026-10-31 00:18:31 | healthy | 402 | 508ms | |
| 2026-10-30 23:12:02 | healthy | 402 | 505ms | |
| 2026-10-30 22:16:53 | healthy | 402 | 577ms | |
| 2026-10-30 21:10:30 | healthy | 402 | 458ms | |
| 2026-10-30 20:15:33 | healthy | 402 | 429ms | |
| 2026-10-30 19:16:11 | healthy | 402 | 312ms | |
| 2026-10-30 18:19:34 | degraded | 402 | 1104ms | |
| 2026-10-30 17:19:13 | healthy | 402 | 1089ms | |
| 2026-10-30 16:21:05 | healthy | 402 | 2516ms | |
| 2026-10-30 15:18:13 | healthy | 402 | 403ms | |
| 2026-10-30 14:19:23 | healthy | 402 | 310ms | |
| 2026-10-30 13:21:30 | healthy | 402 | 493ms | |
| 2026-10-30 12:18:46 | healthy | 402 | 438ms |