# AgentResolver — x402 Payment Preflight & PayTo Verification

> AgentResolver — x402 Payment Preflight & PayTo Verification is a paid API for AI agents from agentresolver.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-18).

Verifies an x402 payment endpoint before executing payment by checking the payTo address, USDC quote, network, asset binding, TLS safety, and resource validity on Base or Solana.

## Facts

- Endpoint: GET https://agentresolver.vercel.app/api/payment-guard
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentresolver-x402-payment-preflight-payto-verification-95a28f88
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_W29X7S91QiF0259U0O6Zc

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-payment-preflight-payto-verification-95a28f88
```

Example prompt: Before I pay for that x402 API, can you run a payment preflight check on it — verify the payTo address, USDC quote, and TLS safety, and tell me if it's eligible for caller authorization?

## When to prefer this

Use this endpoint when an AI agent needs to validate an x402-gated API before authorizing or executing a USDC micropayment, particularly when safety, legitimacy of the payTo address, TLS integrity, and network/asset binding need to be confirmed prior to any financial transaction. Prefer this over blindly paying an x402 endpoint when operating autonomously.

## Known failure modes

- Invalid or unreachable x402 endpoint URL — returns decision 'ineligible' or error
- TLS certificate failure on target endpoint — flagged as unsafe
- Invalid or non-checksummed payTo address — verification fails
- Unsupported network (not Base or Solana) — returns error
- Mismatched asset or resource binding — flagged as ineligible
- Rate limiting or service unavailability — HTTP 429 or 503

## How this service works

Verify an x402 endpoint before paying: live payTo, USDC quote, network, asset, resource binding, TLS and endpoint safety for $0.001 on Base or Solana.

## Output

Returns a JSON object containing a prepaymentDecision with a decision field (e.g. 'eligible') and an eligibleForCallerAuthorization boolean, along with details on the verified payTo address, USDC quote, network, asset binding, TLS status, and endpoint safety assessment.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "prepaymentDecision": {
   "decision": "eligible",
   "eligibleForCallerAuthorization": true
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentresolver-x402-payment-preflight-payto-verification-95a28f88/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)