# ARAKEL x402 Transaction Proof Verifier

> ARAKEL x402 Transaction Proof Verifier is a paid API for AI agents from proof.arakelproof.space, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-13).

Verifies a Base USDC payment transaction and returns a cryptographically signed (Ed25519) binding between that payment and caller-supplied request/response hashes, confirming payee, amount, and confirmations.

## Facts

- Endpoint: POST https://proof.arakelproof.space/v1/x402/transaction-proof?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/arakel-x402-transaction-proof-verifier-f3afcbdb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jAeUseKYwJA-5UaNMPVyF

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability arakel-x402-transaction-proof-verifier-f3afcbdb -d '<json body>'
```

Example prompt: Check whether Base transaction 0xabc123... actually sent 1.50 USDC to wallet 0xPayee456... with at least 3 confirmations, and give me a signed proof that it matches my request hash 0xREQHASH... and response hash 0xRESHASH...

## When to prefer this

Use this endpoint when you need cryptographic, machine-verifiable proof that a specific USDC payment on Base occurred and matches expected parameters (payee, amount, confirmations) AND you want the result cryptographically signed and bound to a request/response hash pair for audit or receipt purposes. Prefer it over generic blockchain explorers when you need a structured, signed assertion an agent or smart contract can consume programmatically, and when operating within x402 payment flows.

## Known failure modes

- Transaction hash not found on Base — transaction_found: false
- Payee address mismatch — payee_matches: false, decision not VERIFIED
- Amount mismatch — amount_matches: false
- Insufficient confirmations at time of check — confirmations_sufficient: false
- Malformed or missing required fields (tx, expected_payee) — validation error
- Network timeout reaching Base RPC — service error

## How this service works

$0.001 OFAC destination-wallet preflight for autonomous agents, plus machine-verifiable official-source evidence over x402 USDC on Base.

## Output

A JSON object containing a 'decision' field (e.g. 'VERIFIED'), a 'verified' boolean, granular 'checks' (payee_matches, amount_matches, transaction_found, transaction_success, confirmations_sufficient), and an Ed25519 'signature' object binding the payment to the supplied request/response hashes, all under the 'arakel.x402.transaction-proof.v1' schema.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "tx": {
   "type": "string",
   "description": "Base transaction hash"
  },
  "service_id": {
   "type": "string"
  },
  "request_hash": {
   "type": "string",
   "description": "SHA-256 style 32-byte request hash for receipt binding"
  },
  "response_hash": {
   "type": "string",
   "description": "SHA-256 style 32-byte response hash for receipt binding"
  },
  "expected_payee": {
   "type": "string",
   "description": "Expected USDC recipient"
  },
  "expected_payer": {
   "type": "string",
   "description": "Optional expected USDC payer"
  },
  "min_confirmations": {
   "type": "integer",
   "maximum": 200,
   "minimum": 1
  },
  "expected_amount_usdc": {
   "type": "string",
   "description": "Expected USDC decimal amount; provide this or expected_amount_atomic"
  },
  "expected_amount_atomic": {
   "type": "string",
   "description": "Expected USDC amount in 6-decimal atomic units; provide this or expected_amount_usdc"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "checks": {
   "payee_matches": true,
   "amount_matches": true,
   "transaction_found": true,
   "transaction_success": true,
   "confirmations_sufficient": true
  },
  "schema": "arakel.x402.transaction-proof.v1",
  "decision": "VERIFIED",
  "verified": true,
  "signature": {
   "alg": "Ed25519"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/arakel-x402-transaction-proof-verifier-f3afcbdb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from proof.arakelproof.space](https://www.zero.xyz/host/proof.arakelproof.space/llms.txt)