$0.01
per call · USD Coin on Base
Compare an agent's advertised contract with its live x402 challenge and return deterministic proof.
Endpoint
POST https://agent-contract-proof.mattskowronis.workers.dev/v1/verify2
Calls / 30d
1
Unique payers / 30d
Aug 31
Last called
exact
Payment scheme
Call this service
import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";
const account = privateKeyToAccount(process.env.PRIVATE_KEY);
const fetchWithPay = wrapFetchWithPayment(fetch, account);
const res = await fetchWithPay("https://agent-contract-proof.mattskowronis.workers.dev/v1/verify", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({
"url": "https://source-claim-proof.mattskowronis.workers.dev"
}),
});
const data = await res.json();curl -X POST \
"https://agent-contract-proof.mattskowronis.workers.dev/v1/verify" \
-H "Content-Type: application/json" \
-d '{"url":"https://source-claim-proof.mattskowronis.workers.dev"}' \
-H "X-PAYMENT: <signed x402 payment>"Example response
{
"checked_at": "2026-01-01T00:00:00.000Z",
"checks": [
{
"evidence_url": "https://example.com/v1/tool",
"expected": "0.01",
"id": "price",
"observed": "0.01",
"status": "pass"
}
],
"contract_hash": "0000000000000000000000000000000000000000000000000000000000000000",
"declared": {
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"evidence_url": "https://example.com/openapi.json",
"input_schema_declared": true,
"method": "POST",
"network": "eip155:8453",
"output_schema_declared": true,
"path": "/v1/tool",
"pay_to": "0x0000000000000000000000000000000000000001",
"price_usd": "0.01",
"source": "openapi"
},
"evidence_urls": [
"https://example.com/openapi.json",
"https://example.com/v1/tool"
],
"mismatches": [],
"observed": {
"amount_atomic": "10000",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"challenge_source": "header",
"http_status": 402,
"network": "eip155:8453",
"pay_to": "0x0000000000000000000000000000000000000001",
"price_usd": "0.01",
"scheme": "exact",
"x402_version": 2
},
"service_version": "1.0.0",
"target_method": "POST",
"target_status": "verified",
"target_url": "https://example.com/v1/tool",
"verdict": "conforms"
}Payment details
0x3a438b911b8e2995a9c855578f95b2889752498fUSD Coin · 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913Is this your API?
Pin it to the top of Other and the homepage with a featured placement.
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