mpp-agent

Install mppx globally with npm, create an account, then run mppx followed by the URL. The client automatically handles the 402 challenge and credential exchange and prints the merchant's actual response on success.

MPP is a protocol where servers respond with HTTP 402 and a www-authenticate header describing payment methods and amounts. Clients like mppx, Tempo Wallet, or Stripe Link pay the challenge and attach a receipt credential to retry the request.

Use Stripe Link CLI when the challenge advertises method="stripe" or the user already has Link configured. Use mppx for one-off paid calls and debugging, and Tempo Wallet when persistent spend controls and service discovery are needed.

No. Stripe Link only pays challenges that advertise method="stripe" in the www-authenticate header. Challenges offering only Tempo or other methods must be paid with mppx or a matching funded wallet.

No. The skill is gated to Linux and macOS platforms while the broader payments tooling matures on Windows. It also requires Node.js 20 or later available on PATH.

Do not use it to add 402 payments to your own API — that is server-side MPP, covered by mppx middlewares for Next.js, Hono, Express, or Elysia. This skill is strictly for paying merchant APIs as a client.