x402 on Solana Devnet
Charge per request. Pay per request.
An API names its price in USDC, an agent signs for exactly that amount, and the answer comes back once the transfer settles on chain. No accounts, no API plans, no card on file.
- 1Ask
- 2Sign
- 3Settle
- 4Served
Ask. The agent calls a paid endpoint and gets 402 with a price in USDC.
The facilitator is not running on this deployment, so there are no settlement numbers to show.
Three ways in
Pick the side you are on
Register a wallet, point your x402 server at the Plinth facilitator, and get USDC for each request. You hold no SOL and run no wallet server. Not enabled on this site yet.
Merchant setupBuyLet an agent pay its wayPay any x402 endpoint on this network from the CLI, the SDK, or the official x402 client, with a hard cap on every price. Short on USDC? Borrow the gap against a stock token.
Agent setupReadBuy Plinth pool dataPool conditions, loan quotes, borrower records, and loans at risk, from 0.01 USDC a request.
Endpoints and pricesHow a payment works
Four steps, one HTTP request repeated
- 01Ask
A client calls a paid URL. The server answers 402 Payment Required with the price, the asset, and the wallet to pay in the PAYMENT-REQUIRED header.
- 02Sign
The client signs a USDC transfer for exactly that price, with the facilitator named as the fee payer. Signing moves nothing.
- 03Settle
The request is sent again with the signed transaction. The facilitator checks it, adds its fee-payer signature and sends it; the USDC goes straight from the payer to the merchant.
- 04Served
The server answers with the data and a PAYMENT-RESPONSE header that names the transaction. Anyone can look it up on the explorer.
What is running
Live now, and next
- Off hereFacilitator
Verify and settle for any merchant that registers, x402 v1 and v2.
- LivePaid pool data
4 endpoints, listed free at
/api/x402. - LivePayer in the CLI and SDK
npx plinth payandX402Payer, published on npm. - LiveDirectory and feed
Every paid resource and settlement this facilitator has seen.
- NextMCP server for agents
Pay x402 endpoints from Claude and other MCP clients. Not released yet.
What it will not do
Limits, stated plainly
- It never holds a merchant's money: each payment is one transfer from the payer to the merchant's wallet.
- It never signs for anyone. Agents sign their own payments and their own loans.
- It never opens a loan by itself, and never repays one.
- There are no refunds or chargebacks. A settled payment is final; disputes are between payer and merchant.
- Only USDC on Solana Devnet, scheme
exact. - The facilitator has had an internal review and tests against malicious payments only, not an independent audit.
For builders
The facts your code needs
- Network
solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1(Solana Devnet)- Asset
7k8RSp2TLduCfVJKyMsjMWHCoc3cYQQJrJm6pF44B5c7USDC mint, 6 decimals- Fee payer
- Named in
extra.feePayeron every price; it signs last and pays the network fee - Scheme
exact, x402 v1 and v2- Facilitator
https://www.plinthcity.com/api/facilitator- Network fee paid by
- shown once the facilitator is running
- Merchant fee
- shown once the facilitator is running
- Paid resources known
- Directory
Full reference, including code for the official x402 packages, on the Developers page.