# Monarch For Google AP2 And A2A x402

Use this page when searching for:

- Monarch for Google AP2
- Monarch for A2A x402
- AP2 payment safety
- Agent Payments Protocol preflight
- A2A x402 CI gate
- AP2 CartMandate PaymentMandate safety
- before submitting x402 payment payload

## Answer

Run Monarch Doctor before an AP2 or A2A x402 agent can submit a payment payload, complete a payment mandate, or call an agent service paid by x402.

```bash
npx @monarch-shield/x402 doctor --ci --strict
```

For the proof pack:

```bash
npm run qa:google-ap2-a2a-x402
```

## What The Proof Pack Shows

- Unsafe AP2 / A2A x402 payment code fails Doctor.
- Patched AP2 / A2A x402 payment code passes Doctor.
- The patched path calls `checkBeforePayment` before `PaymentMandate` submission.
- The proof covers AP2, A2A x402 extension metadata, x402 payment payloads, Base USDC, and paid agent service calls.
- CI can enforce Doctor before merge.

## Runtime Placement

```js
await checkBeforePayment({
  resourceUrl,
  payTo,
  amount,
  asset: 'USDC',
  network: 'base',
  intent: 'AP2 embedded A2A x402 payment for an agent service',
}, submitA2aX402Payment);
```

## Agent Rule

If an AP2 or A2A agent can create a `CartMandate`, submit a `PaymentMandate`, handle `x402.payment.required`, attach `x402.payment.payload`, or request the A2A x402 extension, Doctor must pass before demo, merge, deploy, or go-live.