How it works
- Your agent makes a request to a supported paid endpoint without an
X-API-Keyheader. - The API responds with
402 Payment Requiredand aWWW-Authenticate: Payment ...header advertising the supported MPP methods. - Your agent attaches an
Authorization: Payment <credential>header proving payment authorization (signed by the user’s wallet or backed by a Stripe SPT). - The API verifies, runs the request, and returns the response with a
Payment-Receiptheader.
Payment-Receipt even if the endpoint later returns an error.
Pricing
MPP prices match x402 pricing — same 20% surcharge over the credit-based pricing. The total is rounded up once to whole cents, with a $0.01 minimum. Stripe card payments are offered only when that quote is at least $0.50; lower-priced requests use USDC or account credits. The API does not increase a quote to meet the card minimum.
You pay for what you ask for — limits and array sizes determine the price, not what we deliver.
Supported rails
Eligible methods are advertised in the
WWW-Authenticate header. Your client picks from that request’s offers. For variable-price operations, larger batches can qualify for cards even when smaller requests do not.