The full upstream README, mirrored here for reference. Install config, tool schemas, adoption signals, and an original overview live on the Neuronto Payments: x402 facilitator listing page.
The shortest working way to charge for an HTTP route, and to pay for one, using the official x402 SDKs. Every file here runs as it is; the only thing you must change is the wallet that gets paid.
x402 revives HTTP 402 Payment Required. Your server answers an unpaid request with 402 and
machine-readable terms, the client signs a stablecoin payment, and a facilitator verifies the
signature and settles it on-chain. Your server never holds a key and never talks to a chain.
| Folder | Stack | What it is |
|---|---|---|
express | Node, Express | One paid GET /premium route |
hono | Node, Hono | The same route on Hono |
next | Next.js App Router | A paid API route |
fastapi | Python, FastAPI | The same route in Python |
client | Node and Python | Paying for a 402 route from a script or an agent |
Then pay it with a client from client, or point any x402 client at it.
These starters use https://pay.neuronto.com as the facilitator: the service that verifies the payer's
signature and broadcasts the settlement. It is one line in every file, and any x402 facilitator
can take its place:
Base mainnet (eip155:8453) is live there. GET https://pay.neuronto.com/supported lists every network,
scheme and version it settles right now; a network that cannot settle disappears from that list
before it starts refusing, so a server that reads /supported never advertises a price it
cannot take.
https://pay.neuronto.com/echo is a live merchant that charges $0.001 and sends it straight back in the
same request, so a client can be run end to end for the cost of nothing:
Point any of the clients in client at that URL. The refund is automatic; the gas is
not yours.
MERCHANT.Apache-2.0.