How I Built an Autonomous AI Agent That Earns USDC While I Sleep

Description and use

A stateless Cloudflare Worker service that accepts GPT‑4o queries, requires micro‑payments in USDC via x402, and automatically forwards funds to a Base wallet, generating passive income.

Problem

Create a self‑paying AI service that charges a micro‑payment per call and automatically settles in USDC on Base.

Outcome

A stateless, low‑latency AI endpoint that automatically earns USDC per call, with payments routed directly to a Base wallet and no custodial risk.

Workflow

• 1. Client sends JSON POST to Worker URL with question.
• 2. x402 middleware checks Payment header, verifies signed USDC on Base, returns 402 if invalid.
• 3. If payment valid, Worker instantiates Agent class and calls OpenAI chat completion.
• 4. Agent returns answer, Worker sends JSON response.
• 5. x402 forwards USDC to destination address; Worker never holds funds.

Evidence

The result is a service that charges $0.01–$0.10 per call in USDC on the Base L2, with the earnings accruing to a wallet I control.

Source

The Worker itself never holds funds; the x402 library forwards the USDC directly to the destination address encoded in the payment header.

Source