CompareHow it works
MPP uses HTTP 402 (Payment Required) as a payment challenge. When you call a direct MPP operation without authentication, the server returns anapplication/problem+json response and a WWW-Authenticate: Payment header. Your client pays through Tempo (USDC), then retries the request with a payment credential.
Every response after an accepted payment includes
Payment-Receipt, including non-2xx responses. The receipt confirms settlement, not application success. Challenges and rejected payment credentials do not include a receipt.402 body also advertises an optional accountless guest wallet. The MPP challenge remains unchanged. A failed read creates no checkout. Create a guest Stripe Payment Link only after the user confirms an amount.
No account, API key, or subscription is required. The payment credential authenticates the retried request.
Payment method
MPP payments on Xquik use Tempo with USDC, a dollar-pegged stablecoin. Tempo provides the settlement method for these fixed charges. You need a funded Tempo USDC wallet. See the MPP quickstart for setup instructions.Discovery
MPP discovery metadata is available at:Payment intent
All direct MPP operations use thecharge intent. Each accepted payment settles the fixed price for one request. Xquik does not advertise direct MPP session pricing for result-sized pages.
Eligible endpoints
An accountless guest wallet covers 33 prepaid GET routes, including these 7. See the guest paid-read route inventory. Direct MPP payment credentials and guest keys cannot access monitors, webhooks, extractions, draws, writes, account routes, or account credential routes. API MCP cannot execute guest wallet credential routes.
MPP vs subscription
Next steps
MPP quickstart
Make your first pay-per-use API call.
Authentication
All authentication methods including MPP headers.
Billing & usage
Subscription, guest wallet, and direct MPP pricing.
Guest wallets
Prepay 33 accountless reads with one scoped API key.