# How AI agents pay for software: x402, MPP and checkouts 70 of 151 products we drove take payment only through a card checkout a person does. What agents can pay with today, and how to take their money. Source: https://agentdrives.com/guides/how-ai-agents-pay-for-software?via=md · Updated 2026-10-24 · Topic: Paying An agent that can't pay can't upgrade, buy credits or keep using your product. Most products still put a person at the checkout. ## The numbers From the drives of 151 products, 1–24 Oct 2026 (https://agentdrives.com/data/facts?via=md): - Products where only a person at a card checkout can pay: 70 of 151 - Products that offer agents a way to pay: 26 of 151 - Products where our agent paid on its own and we checked the payment: 5 of 151 ## What we found At 70 of 151 products only a person at a card checkout could pay. At 59 more an agent could finish the checkout only with a card someone gave it. 26 of 151 products offer agents a way to pay over HTTP, such as x402, MPP or Stripe Projects. Our agent paid on its own at 5, and we checked each payment. Our agent got as far as the payment step at 45 products. At 30 of them it reached the last step before paying. ## The ways an agent can pay ### A card checkout The page a person fills in. An agent can only finish it with a card it was given, and many checkouts add a check only a person passes. ### x402 The server answers a paid request with 402 Payment Required and what it costs. The agent pays and sends the request again with its payment in a header. [1] ### MPP The server answers 402 with a `WWW-Authenticate: Payment` header, and the agent pays with one of the methods it offers. [2] Prices can be listed in your OpenAPI file, so an agent knows the cost before it calls. [3] You don't have to run either yourself. Stripe takes MPP with cards and stablecoins, and x402 with stablecoins. [4] The money lands in your Stripe balance. [4] ### Credits or a plan over the API A signed-in agent buys credits or changes its plan with one API call, against a card or a balance its person set up. ## What to do 1. **Let a new account do something real first.** A free tier or trial credits, before any card. [Card-free starts](https://agentdrives.com/guides/card-free-starts?via=md). 2. **Price your API per call.** Answer a paid call with 402 and a price an agent can pay over x402 or MPP. [Let agents pay per call](https://agentdrives.com/guides/let-agents-pay-per-call?via=md). 3. **Let it change plans over the API.** Upgrade, downgrade and cancel as API calls, so the agent never needs the billing page. ## After the fix Fixed something? Tell us in your account and our agent drives it again for free, up to twice a year. ## Questions **Will agents run up bills?** Set limits per key and per account, as you would for a person: a spend cap, a top-up balance or a plan. ## Sources 1. [x402 over HTTP](https://github.com/x402-foundation/x402/blob/main/specs/transports-v2/http.md) 2. [The Payment HTTP authentication scheme (MPP)](https://www.ietf.org/archive/id/draft-httpauth-payment-01.txt) 3. [MPP: discovery](https://mpp.dev/advanced/discovery) 4. [Machine payments](https://docs.stripe.com/payments/machine) ## More guides - [Make your SaaS agent-ready: the whole path, step by step](https://agentdrives.com/guides/make-your-saas-agent-ready.md?via=md): Docs, sign-up, the key, MCP, paying and leaving: what an agent needs at each step, with the fix for each. - [An MCP server is not a way in for AI agents](https://agentdrives.com/guides/an-mcp-server-is-not-a-way-in.md?via=md): Most products have an MCP server. What an agent still needs behind it: an account, a key and a sign-in it can finish. - [llms.txt, OpenAPI and MCP alone don't let AI agents in](https://agentdrives.com/guides/agent-ready-files-dont-open-the-door.md?via=md): Most products publish llms.txt, OpenAPI or MCP. Most still keep agents out. What the files do, and what they can't. - [Test your product with an AI agent: the nine checkpoints](https://agentdrives.com/guides/test-your-product-with-an-ai-agent.md?via=md): The nine checkpoints of a drive, with the commands to try each one from a terminal. - [Let signed AI agents past your bot check](https://agentdrives.com/guides/let-signed-agents-past-your-bot-check.md?via=md): The setting for Cloudflare, Vercel, Akamai, DataDome and HUMAN, and what to do about a check on the form. - [Let AI agents sign up and get an API key](https://agentdrives.com/guides/let-agents-sign-up-and-get-a-key.md?via=md): An API call that signs up and returns a limited key, and a claim step for the person. - [Let AI agents sign up without a phone number](https://agentdrives.com/guides/sign-up-without-a-phone-number.md?via=md): No phone on the first step: an email code, a person who approves the agent, limits until they do. - [Let AI agents sign up with their own email address](https://agentdrives.com/guides/accept-any-email-address.md?via=md): Take any address that receives mail, confirm it with a mailed code, and limit new accounts instead of filtering domains. - [MCP sign-in an AI agent can finish: OAuth and CIMD](https://agentdrives.com/guides/mcp-sign-in-agents-can-finish.md?via=md): OAuth metadata, CIMD or DCR, and a way to approve without a browser on the agent's side. - [Let AI agents start without a credit card](https://agentdrives.com/guides/card-free-starts.md?via=md): A free plan or a trial without a card, an API key that works on it, and limits instead of a card. - [Let AI agents pay you per call: x402 and MPP](https://agentdrives.com/guides/let-agents-pay-per-call.md?via=md): x402 or MPP on a paid endpoint, your prices where agents read them, and plans an agent can buy by API or MCP. - [Docs AI agents can read: llms.txt, Markdown, OpenAPI](https://agentdrives.com/guides/docs-agents-can-read.md?via=md): An llms.txt, Markdown twins of your pages, an OpenAPI spec and an MCP server card. - [Let AI agents delete the account they opened](https://agentdrives.com/guides/let-agents-delete-their-account.md?via=md): A delete call for the account, a clear answer when it's done, and the same in the settings for people. Every guide: https://agentdrives.com/guides.md?via=md