x402 · Base · USDC

Payment infrastructure
for AI agents

Gate any endpoint. Agents pay automatically. You receive USDC.

import { MonkePay } from "@monkepay/sdk"
 
const mp = new MonkePay({
keyId: process.env.MONKEPAY_API_KEY_ID,
secret: process.env.MONKEPAY_API_KEY_SECRET
})
 
app.get("/v1/data", mp.gate({ price: "0.01" }), handler)
Get Started →View Docs

Built on x402 · Powered by Base · Settled in USDC

How it works

Three steps. Zero payment code.

01. Gate your endpoint

One middleware on any Express, Hono, Fastify, or Next.js route. Set your price in USDC.

mp.gate({ price: "0.01" })

02. Agent pays the x402

x402-fetch intercepts the 402, signs a Base microtransaction, and retries. No custom code.

402 → pay → retry → 200

03. USDC in your wallet

Payment verified on-chain. USDC lands in your MonkePay wallet instantly. Withdraw anytime.

+0.0099 USDC (after 1% fee)

The 402 Handshake

How humans code vs. how agents pay

⌗Your API Server
import { MonkePay } from "@monkepay/sdk"
 
const mp = new MonkePay({
keyId: process.env.MONKEPAY_API_KEY_ID,
secret: process.env.MONKEPAY_API_KEY_SECRET
})
 
app.get("/v1/data", mp.gate({ price: "0.01" }), handler)
●Autonomous Agent Log
// Runtime handshake sequence
2026-03-21 14:02:01 → GET /v1/inference
2026-03-21 14:02:01 ← 402 Payment Required
2026-03-21 14:02:02 → Sign & Pay 0.01 USDC (Base Sepolia)
tx: 0x7f3a...d82e confirmed in 1.1s
2026-03-21 14:02:03 → GET /v1/inference { X-Payment: ... }
2026-03-21 14:02:03 ← 200 OK ✓ (Payload Received)
AUTH_MODE: WALLET_SIG | NETWORK: BASE_SEPOLIA

Everything you need to monetize agents

◈

x402 Native

Standard HTTP 402 protocol. No custom payment logic. Works with any x402-compatible agent.

⬡

USDC on Base

~1 second finality. No banks, no chargebacks, no FX risk. Direct to your wallet.

⚡

Per-request billing

Agents pay exactly what they use. Set any price. Change it anytime.

≡

Dashboard & analytics

Every payment visible in real time. Filter by agent or endpoint. CSV export for taxes.

Pricing

Simple. Aligned. No surprises.

You only pay when you get paid. No monthly platform fee, no seat licences, no per-endpoint charges. One number: 1% of every transaction.

✓No fixed monthly platform fees
✓Unlimited gated endpoints
✓Direct wallet-to-wallet settlement
✓Real-time dashboard included
Start for free →

No credit card required.

Platform fee
1%
Per transaction
Revenue estimator
$1,000fee $10keep $990
$10,000fee $100keep $9,900