Machine Payments Protocol (MPP)
stripe.com

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101 points

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bpierre

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5 hours ago

63 comments

neya ・ 4 hours ago

I feel like the word "protocol", is just abused like it is a glorified marketing term. Kind of like how the word "hacker" was abused in everything else that had nothing to do with hacking.

MCP was just a glorified way of tool calling but generated so much hype (and it eventually died down). Now we have MPP. Which again - could have just been another tool call exposed to the agent.

Imagine you hire someone who claimed to have invented a new protocol and you're thinking of something like TCP or UDP, but all they share is just a markdown file.

  • ai-inquisitor ・ 3 hours ago

    The good ol' folks at Stripe's collaborators Tempo Labs tried to make an RFC-style description page for MPP: https://paymentauth.org/ (full doc on IETF draft page: https://datatracker.ietf.org/doc/draft-ryan-httpauth-payment...)

    I almost was going to point it out as evidence there was thought put into it. Nope, it's flimsy and AI generated.

    Also, it contains provisions for scamming customers:

    > 403 indicates the payment succeeded but access is denied by policy

    No, it doesn't explain how to refund payments for customers you deny access to.

    • Xirdus ・ 2 hours ago

      This one is even worse IMO

      > Servers MAY return 402 when:

      > * Offering optional paid features or premium content

      This implies that a successful GET request to a resource that user already does have access to, might still return 402 instead of 200. This makes 402 basically unworkable.

      • pertsix ・ 2 hours ago
        ・ 3 more

        An RFC is a request for comments, contributions.

        Are you open to contributing to this RFC?

        • john_strinlai ・ 22 minutes ago

          that doesnt sound nearly as fun as getting upvotes, if im honest

        • pear01 ・ an hour ago

          Was it AI generated? If so, should I just delegate my AI to do so?

  • devmor ・ 2 hours ago

    I've been thinking this, but never really put it into words.

    Every time I see one of these I think "You are just describing an API".

  • treyd ・ 3 hours ago

    I think this started when "web3" cryptocurrency projects started using the term to pretend that something which isn't much more than a service that uses a blockchain network to move money around was actually somehow "decentralized" and that that made it more trustworthy.

rickydroll ・ 7 minutes ago

As soon as you have a fungible currency, I expect that, from past experience, everyone who carries those packets will stick out a hand for a piece of the action. From a brief read of the description, I also expect attackers to work out a way to drain your account without you noticing.

Regulation E limits your losses for electronic banking. Is this new payment system covered by Regulation E? What is the maximum loss a consumer would experience?

btown ・ 4 hours ago

Jokes about wallet-draining aside, we're already giving our agents a real cash budget that they use for tokens. Our harnesses have mechanisms to manage that spend. And having an easily detectable protocol would allow the harness to ensure that its deterministic code is in play to make these payments - you'd give your payment details to the harness, not to the agent itself.

And as to use cases, if I want quality outputs for automated research and discovery of a topic, in a world where quality journalism/scholarship should be compensated and does use tools like Cloudflare to block automated access, and where AI-generated content is everywhere, it's optimal for me to want to spend some amount of the money I spend on tokens, on the ability for my agent to access reputable primary and secondary sources as needed.

The challenge, of course, is that now there's an incentive for a spam source to try to get my agent to pay it, rather than the actual creator of the content. But there are interesting ways to solve this, because with these payment rails there's now an incentive for alliances of content creators to maintain indices of reputable sources and their canonical domains - perhaps even authoritative hashes of content. Lots of possibilities here.

  • zer00eyz ・ 3 hours ago

    > we're already giving our agents a real cash budget that they use for tokens.

    I read this line and my (poor little) brain ran in a whole other direction for a moment. Because AI token management and "parental controls" aren't that far separated functionally.

    How far are we from the AI companies selling token packs like video games sell premium currency? Buy NOW, 1.99 for 10,000 Anthropic gold...

    • btown ・ 16 minutes ago

      There was another comment I recall from today, discussing how OpenAI is not-so-subtly adopting a social-network-esque model, in how it's fine-tuned its chat system to always suggest another question that the user might want to ask.

      And the gacha gaming industry knows exactly how to monetize this kind of trained instinct in a userbase. One might even call it a sense of pride and accomplishment...

      (But, to my larger point, if agentic harnesses can offer their LLMs a source of reputable input tokens from professional content providers, as an alternative to just more token back-and-forth with the model provider... that harness can at least direct some of that money towards producers of well-researched content.)

    • ccozan ・ 3 hours ago

      Last thing I heard: stock options are so last year, AI companies award ... tokens now. Can't find the source now, sorry!

giovannibonetti ・ an hour ago

For those of you in Brazil, my company jota.ai has built a financial AI-assistant that you can chat with to open a bank account, connect with accounts from other banks, make instant Pix payments with any of them, all of that through WhatsApp right now. We're working hard to release long-running agents soon that can do increasingly complex workflows involving payments and whatnot.

Please let us know if you have suggestions of what complex workflows you would like to build.

sutib ・ 3 hours ago

"they need the ability to transact with businesses and one another."

Really, they _need_ it. How can we possibly live without computers spending money without supervision?

gavinray ・ 4 hours ago

I fail to see how "API call" is anything inherent to Agents/LLMs?

Is this an attempt to get multiple payment processors to adopt the same Payments API so that agents fail less often?

  • ezfe ・ 3 hours ago

    It has nothing to do with Agents/LLMs which is why it's not called "Agentic Payment Protocol."

    It's an API for making purchases instead of interacting with a website of unknown flow.

    • gavinray ・ 2 hours ago

      The text literally starts with:

        > We believe agents will become an integral part of the internet economy, and they need the ability to transact with businesses and one another. 
  > MPP provides a specification for agents and services to coordinate payments programmatically, enabling microtransactions, recurring payments, and more.
      • ezfe ・ 2 hours ago

        Obviously agents are the big thing right now, but that doesn't change the fact that MPP is an automation solution

codeulike ・ 5 hours ago

You're absolutely right! I should have sent $5.00 for that transaction and not $500,000. I will generate a letter for you to print and sign and send to your bank to notify them of my mistake. Would you like me to generate a bankruptcy filing for you as well?

  • ezekg ・ 4 hours ago

    LLMs rarely admit fault, you gotta shift blame onto the user:

    > You're absolutely right! The transaction was submitted as $500,000 instead of $5.00. Since that's what was entered on your end, you'll need to contact your bank to resolve it. I will generate a letter for you to print, sign, and send to your bank if needed. Would you like me to generate a bankruptcy filing for you as well?

    • leptons ・ an hour ago

      Claude always says it is sorry for screwing up when I point out that it screwed up.

      • fragmede ・ 33 minutes ago

        "Never apologize" into the customized instructions seems to work well for that specific issue.

  • leptons ・ an hour ago

    This is the funniest (but seriously not funny at all) thing I've seen on the internet since the start of the whole "AI" craze. And it's all too true.

danlitt ・ 4 hours ago

What does this actually have to do with agents? What does the protocol include that makes this useful with AI rather than just a boring old program?

  • XzAeRosho ・ 4 hours ago

    There's a slightly new topic called Agentic Commerce, where you say for example: "purchase for me the most energy efficient dishwasher with a budget of $600", and the agent will connect via specialized via special MCP Servers and APIs to available stores, and will do the full purchase process for you.

    This MPP helps bridge the gap between the agent putting the product "in the basket", to actually completing the full purchase process.

    Disclaimer: I'm not in any way advocating for this use case, but it's part of my job to understand how it works. Part of what I do is try to help Agents understand, for example, what is "an efficient dishwasher" using actual data, and not hallucinated info.

    • seanmcau ・ 4 hours ago

      I'm probably overlooking something, but what makes the problem of being able to get from item in basket to item is shipping different from choosing which item(s) to put in the basket?

      In other words, if Agents are able to navigate marketplaces, shouldn't that imply they can also navigate a subset of the marketplace, the payment section? Especially given that that section is "easier: theres no need for qualitative (or quantitative) judgement like there is for the shopping portion.

      Perhaps its a matter of proper safeguards?

      • XzAeRosho ・ 3 hours ago
        ・ 2 more

        It's not actually doing browser actions like Playwright or other browser automation tools, rather than direct API and MCP calls/actions. This is a whole new subset of API and connections that are all contained within the Agent context, no browser mocking. That's why they are creating these new protocols, so the full governance can work within the context of the Agent and its available tools.

        As I said, it doesn't have to make sense, but this is being pushed on us anyway...

        • pythonaut_16 ・ 44 minutes ago

          Thanks for sharing your insights!

          It seems like this workflow suffers the same problem as Alexa and Amazon dash buttons: consumers don't typically want the computer to just go buy things for them with no oversight. At least I don't.

          Adding a checkout step would make this more plausible to me. "Agent, go find the most efficient dishwasher under $600" where it adds its recommendation to a cart, or even "Find me the best dishwashers under $600" where it creates a catalog page with its recommendations and an easy checkout process with whatever store is actually providing.

    • twalla ・ 4 hours ago

      As much as I detest having to look at ads or being "influenced" in any way, shape or form, I think the opportunities for exploitation with what you just described is potentially orders of magnitude more harmful. Sure, let me just hand my wallet to a stochastic black box with god-knows-what RL'd biases and then hook it up to adversarial data sources all vying to extract the most money from me - what could possibly go wrong?

  • ezfe ・ 3 hours ago

    That's why it's called Machine Payments Protocol, instead of Agent Payments Protocol

  • uxhacker ・ 4 hours ago

    And would it not be useful to have some kind of human in the middle? For example what is to stop charge backs if no human has actually authorized the transaction?

fhn ・ 2 hours ago

All payments are final. Cancellations and refunds will be charged a 5% processing fee.

NoahZuniga ・ 5 hours ago

Didn't stripe already have a payments protocol?

  • LoganDark ・ 5 hours ago

    MPP's supposed to eventually work with more than Stripe.

glitchc ・ 2 hours ago

It feels like an attempt to bypass PCI-DSS...

xmly ・ 4 hours ago

Fascinating — this is the future of decentralized finance. Agents will be the entities that both earn and consume.

  • 4k0hz ・ 3 hours ago

    "Decentralized" seems like a stretch for something developed and promoted by monolithic payment processors.

  • film42 ・ 4 hours ago

    Maybe. When it comes to actual payments, fee structures don't allow for this outside of the laboratory.

vicchenai ・ 4 hours ago

the real question for me is what happens when agents start hitting premium data APIs with MPP. right now if i want my agent to pull realtime financial data it has to go through my API keys with monthly billing. with MPP the agent could theoretically pay per-query directly to data vendors. thats a much better model for bursty workloads but the authorization problem naomi_kynes raised is real - you need spending caps that the agent cant override, not just logging.

david_shi ・ 5 hours ago

It seems like this is designed for atomic purchases, could it be extended for subscriptions?

  • lihorne ・ 3 hours ago

    Hey, I'm one of the developers at Tempo. We're working on an extension type for subscriptions to propose being added to the spec as well! We're starting with the simple types, but subscriptions are a natural extension. The subscription intent will work similarly to a one-time charge—the server returns a 402 with intent="subscription", and the client signs a recurring authorization.

    • david_shi ・ an hour ago

      Cool, would be nice to get specifics on how payments are processed, failures, and cancellations re: the recurring model.

  • jacobn ・ 5 hours ago

    > MPP provides a specification for agents and services to coordinate payments programmatically, enabling microtransactions, *recurring payments*, and more.

    • david_shi ・ 4 hours ago

      https://docs.stripe.com/payments/machine/mpp

      Yeah I read that copy too, did you read the spec?

      • dabbz ・ 4 hours ago

        I believe the Shared Payment Token is interchangeable with a payment method id that you attach to a customer object, but that link has very sparse information about how things actually work end to end and what objects mean what.

Animats ・ 2 hours ago

"Creates a direct connection between your wallet and our bank account!"

Note the absence of invoices, bills of lading, and receipts, all the things you need when a vendor doesn't deliver. All it does is send money, one-way. So it's useless in a B2B context.

user3939382 ・ 3 hours ago

The more industrial activity and investment I see in “payments” and ecommerce, is to me a signal of a hollow society that has ceased creating real value. We have more to contribute than materialism, skimming off of electronic transactions, entertainment etc.

quantium1628 ・ 2 hours ago

the comments here are better than the article lol

naomi_kynes ・ 4 hours ago

MPP handles 'how do agents pay', but not 'did anyone authorize this'. For low-value API calls that's fine. But once agents start chaining transactions, you need a channel where the agent can ask a human 'I'm about to spend $2k on this, still in scope?' before the payment happens - not a fraud alert after. The authorization layer is a separate infrastructure problem from the payment protocol.