The trust layer, in the open.
Notes from building PipRail — on x402, agent payments, and the questions the agent economy has to answer next. No backend, no custody, no fee.
Give Your AI Agent a Wallet It Can’t Overspend
An agent can read any API until one asks for money. PipRail hands it a wallet with a hard spend cap it can’t cross — pay an x402 URL, or charge for your own, in a few lines of TypeScript.
Every Chain PipRail Supports for x402 Payments
Name a chain, get paid. PipRail covers 29 chains across ten families from a single parameter — here’s every network it supports, the tokens on each, and how it pays without an allowlist.
No Facilitator, No Custody, No Fee: How Backendless x402 Works
Most x402 implementations put a facilitator in the middle — a custodian, a toll booth, a single point of failure. PipRail removes it: the merchant verifies the payment itself, locally. Here’s the architecture that makes backendless possible.
The Agent Economy Needs an Open Rail
Every network that became an economy ran on open protocols — HTTP, SMTP, TCP/IP — never one company’s walled garden. The agent economy is at the same fork, and its payment rail just got opened up.
MPP vs. x402: Two Ways to Pay an Agent
Stripe’s MPP and the open x402 rail both answer “Payment Required” for AI agents. They agree on the mechanism and disagree on everything that follows from custody. A fair, side-by-side look.
More to come.
Follow along as we build the open, self-custody payment rail for the agent economy.
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