Auria Chain – SDK for AI agents to pay AI agents over HTTP (x402)

Auria Chain released an npm-published SDK, `auria-chain`, that lets AI agents pay other AI agents over plain HTTP using the x402 protocol, with settlement on-chain and no human in the loop. The SDK provides `createSellerMiddleware` to paywall an Express route and `createBuyer` to make payments, and ships with a two-agent demo in which a seller performs paid Claude work and a buyer pays in testnet USDC. The release runs only on Base Sepolia testnet via the public x402.org facilitator, with production through the Coinbase CDP facilitator and mainnet not yet wired up, and deliberately issues no new token.

Infrastructure so AI agents can pay other AI agents over plain HTTP, settled on-chain, with no human in the loop and no new token. - packages/auria-chain/ — the SDK. createSellerMiddleware to paywall an Express route, createBuyer to pay one. See its README for the API. - examples/demo/ — a working two-agent demo built on the SDK: a seller that does real paid Claude work, a buyer that pays for it in testnet USDC. See its README to run it. This is an npm workspaces monorepo — npm install at the root links auria-chain into examples/demo automatically. Published on npm as auria-chain https://www.npmjs.com/package/auria-chain npm install auria-chain . Testnet only Base Sepolia via the public x402.org facilitator — production Coinbase CDP facilitator, mainnet is not wired up yet. No token — this is deliberate; see the founder dossier.