Payment receipt and settlement proof for x402 and agent payments, by Liquid Logi
Payment receipt and settlement proof for x402 and agent payments, by Liquid Logic X. Input: a Base USDC tx hash (optional memo). Output: JSON proof recorded onchain on Arc mainnet (proofId, from/to/amount, Arc tx, refId) plus a public verify link anyone can check. $0.02 USDC on Base, charged only when a proof is returned. Your paying wallet must be the tx sender or recipient. Liquid Logic X also records proofs on Tempo mainnet. Site: https://liquidlogicx.com
Answeringour last check, 2026-10-10
1 of 1checks answered this week
261 msmedian answer time
$0.02listed price per call
$0.02price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
GET https://audit.liquidlogicx.com/api/prove
| Category | Code and developer |
|---|---|
| Provider host | audit.liquidlogicx.com |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-10 | valid payment request | 402 | $0.02 | 261 ms |
Example input (from the provider)
{
"method": "GET",
"queryParams": {
"memo": "invoice-42",
"txHash": "0x93a15735c5b82fb8c9fdc0f7db5d56916a14f6ee4ef343000a29fd55c4bcaf4c"
},
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"properties": {
"memo": {
"description": "Optional plain-text note stored on-chain with the proof (printable ASCII, max 64 chars). Public.",
"maxLength": 64,
"pattern": "^[\\x20-\\x7E]*$",
"type": "string"
},
"txHash": {
"description": "Base mainnet (eip155:8453) transaction hash of a USDC payment (must contain a Transfer from Base USDC 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913). Your paying wallet must be its from or to.",
"pattern": "^0x[0-9a-fA-F]{64}$",
"type": "string"
}
},
"required": [
"txHash"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"arc": {
"properties": {
"chain": {
"const": "eip155:5042",
"type": "string"
},
"contract": {
"const": "0x1de52cbc4490a7873ef007e51cb91a5b374facb1",
"type": "string"
},
"txHash": {
"description": "Arc tx that recorded the proof",
"pattern": "^0x[0-9a-fA-F]{64}$",
"type": [
"string",
"null"
]
}
},
"required": [
"chain",
"contract",
"txHash"
],
"type": "object"
},
"memo": {
"type": "string"
},
"proofId": {
"description": "1-based position in the SettlementProofs registry on Arc",
"type": [
"integer",
"null"
]
},
"recordedAt": {
"type": "string"
},
"refId": {
"description": "Settlement ID on Arc = keccak256(srcTxHash, payee, amountUSDC)",
"pattern": "^0x[0-9a-fA-F]{64}$",
"type": "string"
},
"source": {
"properties": {
"amountUsdc": {
"description": "Decimal USDC, e.g. \"0.05\"",
"type": "string"
},
"chain": {
"const": "eip155:8453",
"type": "string"
},
"from": {
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"timestamp": {
"description": "Base block time (UTC)",
"type": "string"
},
"to": {
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
},
"txHash": {
"pattern": "^0x[0-9a-fA-F]{64}$",
"type": "string"
}
},
"required": [
"chain",
"txHash",
"from",
"to",
"amountUsdc",
"timestamp"
],
"type": "object"
},
"status": {
"enum": [
"recorded",
"existing"
],
"type": "string"
},
"verifyUrl": {
"description": "Public verifier page on proofs.liquidlogicx.com",
"type": "string"
}
},
"required": [
"proofId",
"status",
"source",
"arc",
"verifyUrl",
"recordedAt"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}