Pay as you pass.
A per-call payment rail for machine-to-machine APIs. Every request is a toll booth: the gate quotes a price, the caller signs, and it settles on Solana in ~400 ms.
$ curl https://api.mixway.fun/premium ← 402 Payment Required x-toll-ticket: { toll: "$0.002", asset: "USDC", payTo: "13Ev…sTm7" } $ curl -H "x-toll-pass: ‹signed transfer›" … ← 200 OK x-toll-receipt: { tx: "5aUz…5FVt", settled: "0.002 USDC" }
Agents can't reach for a wallet.
Software is starting to call software on its own. An autonomous caller can pay per call — but only if paying is inline, keyless, and instant. That's the gap Mixway fills.
API-key sprawl
Keys, dashboards and monthly invoices don't scale to thousands of autonomous callers making one request each.
Agents have no card
An autonomous caller can't sign up, enter a card, or clear a subscription flow. It just needs to pay and go.
No settlement rail
Micro-payments per call need a rail that settles inline, in milliseconds — not a payout batch run once a month.
Callers pay. Sellers get paid.
The same handshake serves both ends: an autonomous caller settles a request inline, a seller prices a route and collects a payment on-chain.
Pay for a call — no card
- Pay for a call without a card, key, or account.
- Sign a single Solana transfer and retry the request.
- Every paid call returns an on-chain settlement receipt.
Price a URL in one line
- Price any route in one line of middleware.
- The Gate collects the toll before serving a response.
- No keys to issue, no dashboards, no invoices to reconcile.
One rail. Six moving parts.
The protocol is small on purpose. Six composable parts turn any URL into a paid, machine-callable endpoint.
x402 Facilitator
Spec-compliant verify & settle for the exact scheme. Checks the signed transfer, submits it, confirms it.
One-line middleware
Drop into Express, Next, or Hono and price any route. The Gate quotes and collects before your handler runs.
Payment Channel
Batch many tiny tolls into a single on-chain settlement — stream calls, settle once.
Transponder Kit
A client wallet with budget caps and payTo allowlists so an autonomous agent pays safely, on its own.
Escrow & settlement
On-chain escrow, receipts and facilitator bonds — verified in motion, slashable for non-settlement.
Receipt Registry
Every settled call leaves an on-chain receipt — an auditable log of who paid what, to whom, when.
402 → pay → 200 OK.
One HTTP round trip, settled inline. The 402 carries the price; the retry carries the payment.
GET /premium ← 402 Payment Required x-toll-ticket: { scheme: "toll-exact", amount: "2000", asset: "USDC", payTo: "13Ev…" }
// transponder const pass = sign( transfer(payTo, 2000), memo(ticket.nonce), wallet, ) x-toll-pass: "‹signed transfer›"
GET /premium x-toll-pass: … ← 200 OK x-toll-receipt: { tx: "5aUz…", settled: "0.002", asset: "USDC" }
What you can build.
Primitives you can wire together today, from budgeted agents to streaming settlement.
Metered agents
Give an autonomous agent a budget and let it pay per call across any priced endpoint.
Streaming settlement
Meter high-frequency calls off-chain, then batch them into one on-chain settlement.
Facilitator operators
Run a Gate, bond the token to settle payments, and earn a slice of every toll routed through you.
MCP tool payments
Wrap any MCP tool with a toll so agents pay per invocation instead of per subscription.