> ## Documentation Index
> Fetch the complete documentation index at: https://docs.x402r.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Verification and Settlement

> Facilitator verification flow, settlement logic, EIP-6492 wallets, and error codes

## Verification Logic

The facilitator performs these checks in order:

1. **Type guard**: Payload matches `Eip3009Payload` or `Permit2Payload` (includes `signature` and `salt`).
2. **Scheme match**: `requirements.scheme === "auth-capture"` and `payload.accepted.scheme === "auth-capture"`.
3. **Network match**: `payload.accepted.network === requirements.network` and format is `eip155:<chainId>`.
4. **Extra validation**: All required `extra` fields present.
5. **Method routing**: `extra.assetTransferMethod` (default `"eip3009"`) matches the payload shape.
6. **Deadline ordering**: `refundDeadline >= captureDeadline`, `captureDeadline > now + 6s`, and the payload's `validBefore` (EIP-3009) or `deadline` (Permit2) `<= captureDeadline`.
7. **Time window**: `validBefore` / `deadline > now + 6s` (not expired) and `validAfter <= now` (active, EIP-3009 only).
8. **Spender / collector match**: `authorization.to === EIP3009_TOKEN_COLLECTOR_ADDRESS` (EIP-3009) or `permit2Authorization.spender === PERMIT2_TOKEN_COLLECTOR_ADDRESS` (Permit2).
9. **Token match**: `permit2Authorization.permitted.token === requirements.asset` (Permit2 only, EIP-3009 binds via signing domain).
10. **Signature verify**: Recover signer from EIP-712 (`ReceiveWithAuthorization` or `PermitTransferFrom`); must match payer.
11. **Amount**: Authorization amount matches `requirements.amount`.
12. **Nonce match**: Reconstruct `PaymentInfo` from extra + salt + payer + requirements; recompute the payer-agnostic hash; assert it matches the wire nonce. This transitively enforces equality on every field encoded in `PaymentInfo` (receiver, token, deadlines, fee bounds, feeRecipient).
13. **Simulate**: Call `AuthCaptureEscrow.authorize(...)` or `.charge(...)` via `eth_call` to verify success.

The `SAFETY_MARGIN_SECONDS` constant is `6`, which is why deadline comparisons use `now + 6s`.

### EIP-6492 Support

For smart wallet clients, the signature may be EIP-6492 wrapped (containing deployment bytecode). The facilitator extracts the inner ECDSA signature for verification. The on-chain `ERC6492SignatureHandler` in the token collector handles wallet deployment during settlement.

## Settlement Logic

1. **Re-verify** the payload (catch expired/invalid payloads before spending gas).
2. **Determine function**: `extra.autoCapture === true ? "charge" : "authorize"`.
3. **Resolve collector**: `EIP3009_TOKEN_COLLECTOR_ADDRESS` or `PERMIT2_TOKEN_COLLECTOR_ADDRESS` (per `assetTransferMethod`).
4. **Encode `collectorData`**: raw ERC-3009 signature, or ABI-encoded Permit2 signature.
5. **Call escrow**: `AuthCaptureEscrow.<functionName>(paymentInfo, amount, tokenCollector, collectorData)`.
6. **Wait for receipt**: 60s timeout.
7. **Return result**: tx hash, network, payer.

## Error Codes

### Verification Errors

| Error Code                          | Description                                                                       |
| ----------------------------------- | --------------------------------------------------------------------------------- |
| `invalid_payload_format`            | Payload doesn't match `Eip3009Payload` or `Permit2Payload`.                       |
| `unsupported_scheme`                | Scheme is not `auth-capture`.                                                     |
| `network_mismatch`                  | Payload network doesn't match requirements.                                       |
| `invalid_network`                   | Network format is not `eip155:<chainId>`.                                         |
| `invalid_auth_capture_extra`        | Extra is missing required fields.                                                 |
| `unsupported_asset_transfer_method` | `assetTransferMethod` is not `"eip3009"` or `"permit2"`.                          |
| `payload_method_mismatch`           | Payload shape doesn't match `assetTransferMethod`.                                |
| `capture_deadline_expired`          | `captureDeadline <= now + 6s`.                                                    |
| `invalid_deadline_ordering`         | Deadlines violate `now + maxTimeoutSeconds <= captureDeadline <= refundDeadline`. |
| `authorization_expired`             | EIP-3009 `validBefore` (or Permit2 `deadline`) `<= now + 6s`.                     |
| `authorization_not_yet_valid`       | EIP-3009 `validAfter > now`.                                                      |
| `invalid_auth_capture_signature`    | Signature verification failed.                                                    |
| `amount_mismatch`                   | Authorization value doesn't match `requirements.amount`.                          |
| `token_collector_mismatch`          | `to` / `spender` doesn't match the canonical collector for the method.            |
| `token_mismatch`                    | Permit2 `permitted.token` doesn't match `requirements.asset`.                     |
| `nonce_mismatch`                    | Wire nonce doesn't match the recomputed payer-agnostic `PaymentInfo` hash.        |
| `insufficient_balance`              | Payer balance is less than required amount.                                       |
| `simulation_failed`                 | Settlement simulation reverted with an unmapped error.                            |

### Settlement Errors

| Error Code             | Description                                       |
| ---------------------- | ------------------------------------------------- |
| `verification_failed`  | Re-verification before settlement failed.         |
| `transaction_reverted` | On-chain transaction reverted after confirmation. |

## Next Steps

<CardGroup cols={2}>
  <Card title="Wire Format" icon="file-code" href="/x402-integration/auth-capture/wire-format">
    PaymentRequirements and PaymentPayload shapes.
  </Card>

  <Card title="PaymentInfo Struct" icon="cube" href="/x402-integration/auth-capture/payment-info">
    On-chain struct, expiry ordering, and safety guarantees.
  </Card>
</CardGroup>