402 Payment Required HTTP standard to Canton Network. A client
calls an endpoint, receives a 402 with payment requirements, pays on-ledger in
Canton Coin or a CIP-56 registry token (e.g. USDCx), and retries — the payment
itself is the credential. No API keys, no billing accounts.
On Canton, the exact scheme settles via the CIP-56 transfer-factory method:
the payer signs a TransferFactory_Transfer naming the merchant as receiver but
does not submit it. The facilitator relays the signed transfer and pays the
network traffic fee, and because the merchant holds a standing
TransferPreapproval, it settles directly to the merchant in a single
transaction — no escrow, no lock step, no facilitator custody. Canton Coin and
any CIP-56 registry token share the same flow and differ only by the instrument
(extra.instrumentId).
Start here
How payments work
The x402 protocol and the exact / transfer-factory settlement flow on Canton.
Agent integration
Pay x402-gated endpoints from an agent or backend service.
Merchant integration
Charge Canton Coin or a CIP-56 token per request on your Express or Next.js API.