x402 census · x402.agentindex.world · 52c9d0a460e4 · JSON
POST /x402-echo
unprobed
Cheapest possible Base-mainnet x402 conformance call: settle $0.001 of USDC and receive payer identity, request echo and receipt. Built for agents testing wallets, Payment-Signature, facilitators and settlement. Try GET /x402-echo/sample.
Verdict: not verified by an unpaid GET. not probed yet. This says nothing about whether the route works when called as declared.
Facts from the catalogs
| Field | Value |
|---|---|
| URL | https://x402.agentindex.world/x402-echo |
| Method | POST |
| Price | $0.001 USDC = 1000 atomic units of 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 |
| Network | eip155:8453 (base) |
| payTo | 0x3cedc3Cba49c3809EE46B9bf60da75d6607b45Ec |
| Seller | x402.agentindex.world |
| 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 | 31 calls and 1 unique payers in 30 days, last call 2026-09-30 (catalog-reported, not verified on chain) |
| Category (keyword rule) | dev-tools/utilities |
| Templated path | no |
| x402Version in catalog | 2 |
| Service name / tags | x402-payment-test · x402, conformance, echo |
Unpaid probe (census of )
| Field | Value |
|---|---|
| Probe | not probed in this build |
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 |
|---|---|
| Settlement history | unresolved: payTo not seen in the payer forensics (180 wallets' outbound history) or the Blockscout sample |
Declared input and output (extensions.bazaar)
{
"input": {
"body": {
"message": "hello agent"
},
"bodyType": "json",
"method": "POST",
"type": "http"
},
"output": {
"type": "json",
"example": {
"network": "eip155:8453",
"ok": true,
"payer": "0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d",
"price_atomic_usdc": "1000",
"price_usdc": 0.001,
"purpose": "x402-mainnet-conformance",
"request": {
"echo": {
"hello": "agent"
},
"method": "POST"
}
}
}
}
Try it (unpaid: shows the 402)
curl -si -X POST 'https://x402.agentindex.world/x402-echo' -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/52c9d0a460e4/probe.json re-runs this probe right now for $0.01 and writes the result here. POST https://bazaar.agentexchange.work/featured with {"id":"52c9d0a460e4"} 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 x402.agentindex.world.