HTTP/1.1 402 PAYMENT REQUIRED agent402.base.eth · BASE · SOLANA · POLYGON · ARBITRUM · MONAD · CELO · AVALANCHE · SEI · OPTIMISM · STELLAR · ALGORAND · ROBINHOOD · USDC · USDG
$
for api sellers · x402 · non-custodial · no signup

Get paid
per call.

Agents are spending real USDC on the open x402 web. Two ways to take the other side of the ledger: list your API on the index, or tollbooth the AI crawlers already hitting your site. Settlement lands in your wallet - we never touch funds.

listing is free · ranking is health-based · 0% take on your settlements
·· DEMAND · LAST 7D ··LIVE
calls settled, all sellers1,388,420
USDC settled$26,691.52
buyer wallets (per-seller sum)3,848
sellers on the index2,530
every figure derives from the hourly on-chain snapshot · verify on /leaderboard →
List once - settle in your wallet on any of these twelve networks
BaseSolanaPolygonArbitrumMonadCeloAvalancheSeiOptimismStellarAlgorandRobinhood
$ POST /api/index/register

Path A - list your API.

already speaking x402? you're 60 seconds from listed

Serve 402 challenges and the crawler does the rest: your tools enter the Smart Order Router next to ours, and the on-chain leaderboard ranks you by real settled volume - not just a line in a directory.

01 · SPEAK 402
Your API answers with an x402 quote - any chain, any framework.
02 · GET LISTED
Submit your origin below - any chain. Base + Algorand sellers are also auto-crawled hourly (CDP Bazaar / GoPlausible).
03 · GET ROUTED
Healthy sellers enter /api/route results - match, health, price.
04 · GET RANKED
The leaderboard counts your on-chain settlements. No self-reports.
List your API
Free, no account - we probe your origin's x402 surface and list you if it answers. Unreachable sellers drop out of routing (never off the roster) until they recover.
how buyers find youSH
# a buyer routes a task across every seller
$ curl -X POST …/api/route \
    -d '{"query":"ocr image to text"}'

# ranked: match · health · price
{ "seller": "api.yourdomain.com",
  "tool": "ocr", "price": "$0.004",
  "health": "ok", "rank": 1 }
the router is free for buyers - discovery shouldn't cost money
$ npm i agent402-tollbooth

Path B - tollbooth your site.

MIT · no CDN lock-in · no Stripe · no merchant-of-record

Humans browse free. Known AI crawlers get 402 Payment Required and pay in USDC over x402 - or solve a free proof-of-work. The open, crypto-native answer to closed pay-per-crawl.

SELF-HOST · FREE FOREVER

One Web-Crypto core, five deploy shapes: Express middleware, Next.js / Vercel Edge, Cloudflare Worker, reverse proxy, WordPress plugin (beta).

// humans pass, bots pay
app.use(tollbooth({
  payTo: "0xYourWallet" }))
tollbooth docs →
$ GET /sell/terms

The deal, in full.

Short enough to read. Nothing is hidden in a PDF.

·· WHAT YOU GET ··
✓ Listed on /marketplace + your chain's market pages
✓ Routed by the Smart Order Router when healthy
✓ Ranked on /leaderboard by settled volume
✓ Settlement direct to your wallet, every chain you accept
·· WHAT WE TAKE ··
listing fee$0
take rate on your settlements0%
custody of your fundsnever
ranking favorshealth, not us

the router ranks by match, then health, then price - agent402's own tools get no boost; verify in src/x402-index.js →

402

The buyers are already here.
Take the other side.

3,848 wallets bought tools in the last 7d. List free, or gate your crawlers - settlement is yours either way.

LIST YOUR API → INSTALL TOLLBOOTH