# RelayHop Payment Verifier

> RelayHop Payment Verifier is a paid API for AI agents from payment-verifier.relayhop.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Verifies an on-chain transaction on the Base network by transaction hash, returning structured signals including verification status, amount, sender, recipient, block number, and confirmation timestamp.

## Facts

- Endpoint: GET https://payment-verifier.relayhop.workers.dev/v1/check
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/payment-verifier-relayhop-workers-dev-1cd30b29
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kDMMJ4VBdKt4Dtz3SIyR_

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 payment-verifier-relayhop-workers-dev-1cd30b29
```

Example prompt: Can you verify that this Base transaction went through and tell me the sender, recipient, amount, and whether it's confirmed? The tx hash is 0x4a3f2e1b9c8d7a6f5e4d3c2b1a0f9e8d7c6b5a4f3e2d1c0b9a8f7e6d5c4b3a2f1.

## When to prefer this

Use this endpoint when you need real-time, structured on-chain verification of a specific Base network transaction — particularly useful for confirming payment receipt before fulfilling an order, validating sender/recipient correctness, or getting block-level confirmation proof. Prefer this over general blockchain explorers when you need programmatic, structured output with semantic signals rather than raw RPC data.

## Known failure modes

- Invalid or malformed transaction hash returns error or unverified status
- Transaction not yet mined returns verified: false with no block_number
- Transaction on wrong chain (not Base) may return unverified or empty result
- Network/RPC downtime may cause timeout or 5xx error
- Payment failure (insufficient USDC balance) prevents the check from being performed

## How this service works

Real-time on-chain payment verification and check via Base RPC. Returns structured signals: verified status, amount, sender, recipient, transaction confirmation, block number. Pay $0.005 USDC per check. Covers payment, transaction, address, contract, score, signals.

## Output

Returns a structured object with: verified (boolean), tx_hash, amount, asset, chain, sender address, recipient address, block_number, confirmed_at timestamp, and an array of signals (e.g. 'confirmed', 'correct_recipient', 'expected_amount').

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {
   "tx": "0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef"
  }
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "tx"
     ],
     "properties": {
      "tx": {
       "type": "string",
       "description": "Transaction hash (0x + 64 hex chars)"
      }
     }
    }
   }
  },
  "output": {
   "type": "object",
   "properties": {
    "asset": {
     "type": "string"
    },
    "chain": {
     "type": "string"
    },
    "amount": {
     "type": "string"
    },
    "sender": {
     "type": "string"
    },
    "signals": {
     "type": "array",
     "items": {
      "type": "string"
     }
    },
    "tx_hash": {
     "type": "string"
    },
    "verified": {
     "type": "boolean"
    },
    "recipient": {
     "type": "string"
    },
    "block_number": {
     "type": "number"
    },
    "confirmed_at": {
     "type": "number"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/payment-verifier-relayhop-workers-dev-1cd30b29/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from payment-verifier.relayhop.workers.dev](https://www.zero.xyz/host/payment-verifier.relayhop.workers.dev/llms.txt)