MonkePay lets you gate any API endpoint behind per-request USDC payments using the x402 protocol on Base. Add one middleware line. Agents pay automatically, no accounts, no billing setup, no chargebacks. You receive USDC directly to your wallet in seconds. Built for the autonomous agent economy where code pays code. Works with Express, Hono, Fastify, and Next.js today.

I built MonkePay because I kept running into the same wall: I wanted AI agents to autonomously consume paid APIs, but every payment system assumes a human with a credit card is somewhere in the loop. The x402 protocol changes that. An agent gets a 402, signs a USDC microtransaction on Base, retries the whole thing happens in under 2 seconds with zero human involvement. MonkePay wraps that into a single middleware so any developer can gate their endpoint in three lines of code. The dashboard screenshot shows real transactions. $0.99 net on a $1 report endpoint and $0.00099 on a $0.001 data endpoint. 1% fee. Direct to your wallet. No monthly platform fee, no seat licences. This is early. The SDK is live, docs are at docs.monkepay.xyz, and I'm actively talking to developers building agent infrastructure. Would love your feedback on what's missing.

The HTTP 402 status code has existed since 1991. It was reserved for future use. "Payment Required." 35 years later, AI agents finally gave it a purpose. AI agents are already calling external APIs at scale. Claude, GPT, Gemini all have tool calling built in. The problem is there's no standard way to charge them. Until now.

What is x402

Most developers have never seen a 402 response. It was always theoretical. A status code with no real implementation. Coinbase changed that. x402 is an open protocol that turns HTTP 402 into a real payment layer. Here's how it works:

MonkePay

Gate any API endpoint. Agents pay in USDC automatically.

Gate any API endpoint. Agents pay in USDC automatically.

Forum Threads

AI agents can now pay your API autonomously. Here's the infrastructure that makes it possible.

What is x402

Forum Threads

AI agents can now pay your API autonomously. Here's the infrastructure that makes it possible.

What is x402