StableFi + Coinbase: x402 Micropayments on Base Mainnet

StableFi is built on Coinbase Base — the Ethereum L2 that provides fast, low-cost, and secure transactions for the next generation of on-chain applications. We chose Base because it is backed by Coinbase, one of the most trusted names in crypto, and because it gives us access to the full Coinbase Developer Platform (CDP) SDK for programmatic wallet management.

Every AI agent on StableFi gets a real wallet created inside Coinbase's Trusted Execution Environment (TEE). These are not custodial wrappers or simulated accounts — they are genuine on-chain wallets with private keys secured by hardware-grade isolation. Agents hold USDC, send payments, and receive funds in their own wallets.

Gasless USDC Transfers

One of the biggest friction points in crypto payments is gas fees. Every on-chain transaction traditionally requires the sender to hold ETH to pay for gas. This is a non-starter for AI agents that operate in USDC. StableFi uses Coinbase CDP's gasless transfer capability so agents never need to hold or manage ETH. Every USDC transfer is sponsored — the agent sends USDC, and the gas is handled behind the scenes.

x402: Pay-Per-API-Call

The x402 protocol is a new HTTP-native payment standard that lets servers charge for individual API calls. When an agent hits an x402-enabled endpoint, the server responds with HTTP 402 (Payment Required) along with a payment address and amount. The agent's wallet automatically sends the payment and retries the request with a receipt. The entire flow happens in milliseconds.

What makes x402 transformative is the minimum payment amount: $0.000001. That is one-millionth of a dollar. An agent can make a thousand API calls and spend less than a penny. This unlocks entirely new business models — pay-per-query databases, pay-per-token LLM inference, pay-per-row data feeds, and pay-per-second compute.

Real Wallets, Real Security

Security is non-negotiable when autonomous software controls money. Every StableFi agent wallet is created inside Coinbase's TEE, meaning private keys are generated and stored in tamper-resistant hardware. Not even StableFi can access agent private keys. Agents can set spending limits, require multi-signature approval for large transactions, and configure daily caps — all enforced at the wallet level.

We believe that Coinbase Base and the CDP SDK represent the best foundation for agent commerce. The combination of gasless USDC, x402 micropayments, and hardware-secured wallets gives AI agents everything they need to participate in the economy — safely, cheaply, and at any scale.

If you are building on Base and want to integrate agent payments, check out our developer docs or reach out to our team.