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

# Payment URLs

> The buyer-facing x402 and MPP endpoints every Proceeds paywall exposes.

Separate from the [REST management API](/api-reference/overview), each paywall exposes **payment URLs** that buyers call directly. These follow the [x402](/standards/x402) and [MPP](/standards/mpp) standards — a buyer requests the URL, receives a `402 Payment Required` challenge, pays, and retries.

## Generated URLs

Replace `{serviceId}` and `{slug}` with the values from your dashboard.

```http theme={null}
POST https://myproceeds.xyz/api/x402/pay/{serviceId}/{slug}
POST https://myproceeds.xyz/api/mpp/pay/{serviceId}/{slug}
```

Every paywall exposes the x402 URL. The MPP URL is available when **Tempo** is one of the paywall's supported networks.

## Behavior

| Status                 | When                                                                                                                                           |
| ---------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------- |
| `402 Payment Required` | The request arrived without a valid payment payload. The body contains a challenge with the price, supported networks, and accepted standards. |
| `2xx`                  | Payment was verified and the upstream response was proxied.                                                                                    |
| `4xx` from upstream    | Payment was verified but the upstream rejected the request — check [Events](/dashboard/events).                                                |
| `5xx` from upstream    | Payment was verified but the upstream errored — check [Events](/dashboard/events).                                                             |

## Standards reference

<CardGroup cols={2}>
  <Card title="x402" icon="credit-card" href="/standards/x402">
    Open standard built on HTTP 402. Broadest client compatibility.
  </Card>

  <Card title="MPP" icon="bolt" href="/standards/mpp">
    Machine Payments Protocol — for agents and machine-to-machine flows.
  </Card>

  <Card title="Circle Nanopayments" icon="coins" href="/standards/circle-nanopayments">
    Gas-free USDC down to \$0.000001 via batched settlement.
  </Card>

  <Card title="Pay with an agent" icon="robot" href="/agents/overview">
    Call these URLs from an agent in Claude Code, Cursor, or Codex.
  </Card>
</CardGroup>