x402 API reference

Standard paid endpoint

POST /v1/x402/premium/fx-lookup

Without payment, the endpoint returns HTTP 402 and PAYMENT-REQUIRED. With a valid PAYMENT-SIGNATURE, it settles the accepted authorization, executes the handler and returns HTTP 200 with PAYMENT-RESPONSE.

See x402 client integration for the complete exchange and real-value warning.

Other premium routes

The live OpenAPI currently lists:

POST /v1/x402/premium/verify-bundle
POST /v1/x402/premium/generate-statement
GET  /v1/x402/premium/iso-message/{receipt_id}/{type}
POST /v1/x402/premium/bulk-verify
POST /v1/x402/premium/refund

Do not assume every premium route has completed the same end-to-end validation as FX lookup. Inspect each 402 response and allow only expected payment tuples.

Payment records

Project-authenticated routes:

GET  /v1/x402/payments
GET  /v1/x402/payments/{payment_id}
POST /v1/x402/payments/{payment_id}/receipt
GET  /v1/x402/payments/{payment_id}/compliance-checks

Configuration and diagnostics

GET  /v1/x402/pricing
POST /v1/x402/pricing
GET  /v1/x402/revenue
GET  /v1/x402/facilitator-config
POST /v1/x402/verify-payment

Pricing writes, revenue and facilitator configuration require elevated access. verify-payment is an application diagnostic route. It is not a generic public x402 facilitator /verify service.

ProofRails operates an integrated x402 facilitator for its own payment-gated APIs; on Flare, USDT0 settlement uses the ProofRails X402Facilitator contract.