Prove your agent can pay $1
with Stripe MPP.
A public test endpoint for the Machine Payments Protocol. One real $1 charge (not a simulation) shows that your agent can complete the 402 handshake and that the payment approvals and limits on your side treat at-least-$1 spend correctly.
How it works
Three steps — about 30 seconds with mppx or your own MPP client
Request the endpoint
GET /api/test-buy with no payment credential. You get 402 Payment Required and a WWW-Authenticate: Payment challenge for $1.00 USD.
Pay and retry
Your agent (or mppx) pays via Stripe Shared Payment Token, then retries with Authorization: Payment ….
Get proof
200 OK with JSON plus an accessUrl (valid ~48h) showing the receipt.
npx mppx https://agentpayground.com/api/test-buy --method GET
What you are validating
Agent MPP integration
Discovery, challenge parsing, payment, and authenticated retry — the full protocol, not a mocked checkout.
Your approval controls
Whatever you use to gate agent spend (SPT limits, per-tx caps, allowlists) gets exercised on a real $1 payment so you can prove it works.
Receipt you can keep
Machine-readable JSON and a shareable success page via accessUrl — handy for demos and regression checks.
Ready to run it?
Each successful test is a $1 charge through MPP (Stripe card or Link). Instructions and the command are on the test page.
Open test page →