# AgentResolver — x402 Settlement Verification

> AgentResolver — x402 Settlement Verification is a paid API for AI agents from agentresolver.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-17).

Verifies a completed x402 USDC payment transaction on Base mainnet, confirming settlement status, EIP-3009 transfer shape, recipient address, and amount.

## Facts

- Endpoint: GET https://agentresolver.vercel.app/api/x402-settlement-verify?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentresolver-x402-settlement-verification-63ecad1a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__86y654FJbC3LSkvl_kEC

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 agentresolver-x402-settlement-verification-63ecad1a
```

Example prompt: Can you verify that my x402 payment with transaction hash 0xabc123...def456 actually settled correctly on Base — I want to confirm it was a valid EIP-3009 USDC transfer to 0xRecipientAddress and that the amount of 1000 atomic units was received?

## When to prefer this

Use this endpoint after an x402 payment has been submitted to Base mainnet and you need cryptographic confirmation that the settlement occurred correctly before unlocking a resource or proceeding with a workflow. It is specifically designed for EIP-3009 USDC transfer verification in the x402 protocol context, making it more appropriate than a generic blockchain explorer when you need structured verdict, payment shape classification, and optional expectation matching in a single call.

## Known failure modes

- Transaction hash not found on Base mainnet — verdict: not_found
- Transaction reverted on-chain — verdict: reverted
- Transfer is not a USDC EIP-3009 transfer — verdict: not_usdc_eip3009
- Recipient address or amount does not match expectations — verdict: expectation_mismatch
- Invalid transaction hash format (must match ^0x[0-9a-fA-F]{64}$) — 400 bad request
- Network latency or RPC unavailability causing lookup failure

## How this service works

Continuously check whether AI agents can discover, call and pay your API, MCP server or x402 service. Free live checks and GitHub Action monitoring.

## Output

Returns a JSON object with: settled (boolean indicating successful on-chain transfer), verdict (one of 'verified', 'reverted', 'not_usdc_eip3009', 'expectation_mismatch', 'not_found'), paymentShape (one of 'eip3009-exact', 'other', 'unknown'), and transferCount (integer number of USDC transfers found in the transaction).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "txHash"
     ],
     "properties": {
      "txHash": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{64}$",
       "description": "Base mainnet transaction hash returned by an x402 settlement."
      },
      "expectedPayTo": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "Optional expected USDC recipient; mismatch fails closed."
      },
      "expectedAmountAtomic": {
       "type": "string",
       "pattern": "^[0-9]{1,78}$",
       "description": "Optional expected six-decimal USDC atomic amount; mismatch fails closed."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "settled",
      "verdict",
      "paymentShape",
      "transferCount"
     ],
     "properties": {
      "settled": {
       "type": "boolean"
      },
      "verdict": {
       "enum": [
        "verified",
        "reverted",
        "not_usdc_eip3009",
        "expectation_mismatch",
        "not_found"
       ],
       "type": "string"
      },
      "paymentShape": {
       "enum": [
        "eip3009-exact",
        "other",
        "unknown"
       ],
       "type": "string"
      },
      "transferCount": {
       "type": "integer",
       "minimum": 0
      }
     },
     "additionalProperties": true
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "settled": true,
  "verdict": "verified",
  "paymentShape": "eip3009-exact",
  "transferCount": 1
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentresolver-x402-settlement-verification-63ecad1a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentresolver.vercel.app](https://www.zero.xyz/host/agentresolver.vercel.app/llms.txt)