mppx

TypeScript SDK for the "Payment" HTTP Authentication Scheme. Full 402 flow: challenge → credential → receipt.

Client

import { Mppx, tempo } from 'mppx/client'

// Polyfills globalThis.fetch to handle 402 automatically
Mppx.create({
  methods: [tempo({ account })],
})

const res = await fetch('https://api.example.com/resource')

Without polyfilling:

const mppx = Mppx.create({
  methods: [tempo({ account })],
  polyfill: false,
})

const res = await mppx.fetch('https://api.example.com/resource')

Server

import { Mppx, tempo } from 'mppx/server'

const mppx = Mppx.create({
  methods: [tempo({ currency: '0x...', recipient: '0x...' })],
  secretKey: process.env.MPP_SECRET_KEY,
})

async function handler(request: Request): Promise<Response> {
  const result = await mppx.charge({ amount: '1.00' })(request)
  if (result.status === 402) return result.challenge
  return result.withReceipt(Response.json({ data: '...' }))
}

Methods

Method	Intent	Description
tempo.charge	charge	One-time stablecoin payment (TIP-20 token transfer on Tempo)
tempo.session	session	Streaming payments via payment channels on Tempo
stripe.charge	charge	One-time payment via Stripe

tempo() returns [tempo.charge, tempo.session] as a tuple. Use tempo.charge() or tempo.session() individually if you only need one intent.

Exports

Path	Purpose
mppx	Core primitives (Challenge, Credential, Method, Receipt, PaymentRequest)
mppx/client	Mppx, tempo, stripe, session, Transport
mppx/server	Mppx, tempo, stripe, Transport, Store, NodeListener
mppx/hono	Hono middleware
mppx/express	Express middleware
mppx/nextjs	Next.js middleware
mppx/elysia	Elysia middleware

CLI

mppx includes a CLI for making paid requests during development:

npx mppx account create        # create wallet
npx mppx mpp.dev/api/ping/paid # make paid request
npx mppx example.com -v        # verbose output

References

• Docs: https://mpp.dev/sdk/typescript
• Repo: https://github.com/wevm/mppx
• Spec: https://github.com/tempoxyz/payment-auth-spec
• Tempo: https://docs.tempo.xyz