# MPP

Category: Commerce

## Goal
Publish an OpenAPI document at /openapi.json with `x-payment-info` extensions on payable operations. Each operation should declare `intent` (charge or session), `method` (tempo, stripe, lightning, card), `amount`, and `currency`. Use the MPP SDK (`mppx` for TypeScript, `pympp` for Python) with framework middleware for Hono, Express, Next.js, or Elysia to handle the payment flow.

## Validation
- Use public machine-readable artifacts where the standard expects them.
- Confirm content types, payload shape, and discoverability from the public web surface.
- Keep the implementation read-only from the scanner perspective.

## Copyable Fix Prompt
```text
Fix the MPP gap for https://example.com.

Requirements:
- Publish an OpenAPI document at /openapi.json with `x-payment-info` extensions on payable operations. Each operation should declare `intent` (charge or session), `method` (tempo, stripe, lightning, card), `amount`, and `currency`. Use the MPP SDK (`mppx` for TypeScript, `pympp` for Python) with framework middleware for Hono, Express, Next.js, or Elysia to handle the payment flow.
- Preserve existing product behavior and do not do UI work.
- Use machine-readable public artifacts under /.well-known/ or response headers when appropriate.
- Add or update automated tests covering the new behavior.
- Validate the final response shape and content types.
```