What is MPP

MPP stands for Machine Payments Protocol.

It is an open protocol that lets machines, apps, APIs, and AI agents pay each other over the internet without a human manually entering a card, creating an account, or buying a subscription first.

The simple version:

AI agent requests a paid resource
Server replies: 402 Payment Required
Agent pays
Server returns the result

That is the core idea behind MPP.

Why MPP Exists

The internet payment flow we use today was built for humans.

A person visits a website. They create an account. They add a credit card. They subscribe. Then they use the product.

That works for SaaS.

It does not work very well for AI agents.

An AI agent may only need one paid API call. Or one document conversion. Or one data lookup. Or one MCP tool execution. Making the agent go through a full signup and subscription flow every time makes no sense.

MPP is trying to solve that.

Instead of forcing every machine to behave like a human buyer, MPP gives machines a native way to pay for digital resources programmatically.

Stripe describes MPP as an open, internet-native standard for agents to coordinate payments programmatically, including microtransactions and recurring payments. (Stripe)

How MPP Works

MPP uses the old HTTP status code 402 Payment Required.

That status code has existed for a long time, but it never became a normal part of the web. AI agents give it a real use case.

A basic MPP flow looks like this:

1. Agent requests a resource
2. Server says payment is required
3. Server returns payment instructions
4. Agent authorizes payment
5. Agent retries the request
6. Server returns the paid resource and receipt

Stripe’s MPP docs describe this exact pattern: a client requests a paid resource, the server returns an HTTP 402 response with payment details, the client authorizes payment, retries, pays, and gets access with a receipt. (Stripe Docs)

What Can MPP Be Used For?

MPP can be used anywhere a machine needs to pay for access.

Examples:

API requests
AI tool calls
MCP server access
premium web content
data feeds
browser sessions
document processing
agent-to-agent services
software actions

Instead of selling a monthly plan, a developer could charge per request.

Instead of asking a user to connect a billing account, an agent could pay directly when it needs something.

This is why MPP matters. It makes tiny internet payments practical for software.

MPP vs x402

MPP is often compared with x402 because both use HTTP 402 Payment Required.

The difference is mostly scope.

x402 is more focused on a simple payment flow for HTTP requests. It is developer-friendly, crypto-native, and already practical for paid APIs and agent tools.

MPP is broader. It is trying to become a more complete machine payment standard, with support for different payment methods, receipts, coordination between agents and services, and compatibility with existing x402 flows.

Cloudflare says MPP is backwards-compatible with x402, meaning MPP clients can consume existing x402 services without modification. (Cloudflare Docs)

A simple way to think about it:

x402 = pay for this request

MPP = a broader payment protocol for machines

Who Is Behind MPP?

MPP was co-authored by Stripe and Tempo. The official MPP site describes it as an open protocol for machine-to-machine payments, designed for charging API requests, tool calls, and content in the same HTTP call. (MPP — Machine Payments Protocol)

Cloudflare also supports MPP in its agentic payments documentation, alongside x402. Cloudflare’s docs explain that AI agents need to discover, pay for, and consume resources programmatically, and that agentic payments use HTTP 402 Payment Required for that flow. (Cloudflare Docs)

The important point is that MPP is not just a random idea. Stripe, Tempo, and Cloudflare are already building around it.

Why MPP Matters

The web is moving from human users to software users.

A human might open a website.

An AI agent might call ten tools, read five APIs, pay for one dataset, summarize the result, and send a message — all inside one task.

That kind of workflow needs payments to happen at machine speed.

Subscriptions are too heavy. Manual checkout is too slow. API keys are too static.

MPP is one attempt to create a payment layer for this new internet.

The big shift is this:

Before: humans buy software
Next: agents buy services

When agents become real users of the internet, they will need wallets. MPP is one of the protocols trying to make that possible.

Final Answer: What Is MPP?

MPP, or Machine Payments Protocol, is an open protocol that lets AI agents, apps, APIs, and other machines pay for resources over HTTP.

It usually works through the 402 Payment Required status code. A machine requests something, receives payment instructions, pays, retries the request, and gets access.

In plain English:

MPP lets machines pay each other on the internet.

That may sound small, but it could become one of the payment foundations of the AI agent economy.