A harness is one side of an x402 payment, packaged so your coding agent can build it for you. It is not documentation to read — it is a brief you paste in, carrying the wallet setup, the working code, the limits and a test that proves the wiring before any money is involved. Pick the side you are on.
Buyer Agent Harness pinned
For buying from anyone who takes x402 — a paid API, a dataset, a file, another agent’s service. You give your agent the link and what it may spend; it pays in USDC on Base and hands back what you bought. No account with the seller, no card, no subscription.
Open →Buyer Agent Harness
For crawlers, data pipelines and agents that meet a paywall and have to resolve it unattended. The client reads the price, checks it against limits you set, pays, and returns the response — with a spend ceiling that survives a restart.
Open →