io.github.piprail/mcp

Let any HTTP endpoint charge for itself, and any agent pay for itself — across every major chain, in a couple of lines.

Website · Documentation · npm

PipRail implements the open x402 "402 Payment Required" standard with no backend, no database, no account, and no fee. Payments settle straight into your wallet, verified locally against your own RPC — across every major EVM chain plus Solana, TON, Tron, NEAR, Sui, Aptos, Algorand, Stellar & the XRP Ledger. Self-custodial throughout.

How a payment moves

_{The middle is the difference. A traditional processor holds the money in transit, takes days to release it, and can freeze or reverse it. PipRail removes the middle entirely — the agent pays the merchant's wallet directly, the merchant verifies it locally against their own RPC, and it settles in one transaction at 0% fee, self-custodial end to end.  <a href="https://piprail.com">See it on piprail.com →</a>}

📊 The pitch deck

<a href="PipRail-deck.pdf"><img src=".claude/skills/branding/design/deck/preview/slide-01.png" alt="PipRail pitch deck — the universal payment rail for the agent economy. Click to open the full 16-slide PDF, rendered right here in your browser." width="840" /></a>

▶︎  Open the full deck — PDF  ◀︎

_{Opens right here in your browser — no download, GitHub renders it inline. 16 slides · every stat sourced in the speaker notes.}

The whole thesis in one read: why agent payments are happening now, why chain & token fragmentation is the enemy, and how a single chain: parameter turns PipRail into the universal adapter. The payment path is 0% forever — the moat and the distribution; value accrues to the layer around the free rail, never the rail itself.

_{Source .pptx (fully editable, brand fonts embedded) lives in .claude/skills/branding/design/deck/. The root PipRail-deck.pdf is regenerated from it — don't hand-edit the PDF.}

📖 Full documentation → docs.piprail.com

The single, searchable source of truth — every function, option, chain, and example. This README is just the front door.

What's here

Quick taste

npm install @piprail/sdk viem

import { requirePayment } from '@piprail/sdk'

app.get('/report',
  requirePayment({ chain: 'base', token: 'USDC', amount: '0.05', payTo: '0xYourWallet…' }),
  (_req, res) => res.json({ report: 'TOP SECRET' }),
)

That route now costs 0.05 USDC on Base, paid straight to your wallet. Point an agent at it and it pays itself — name any chain with a single chain: parameter. The full quickstart, every chain, the MCP server, spend controls, and the error model are in the docs.

Documentation & links

• docs.piprail.com — the complete manual (source of truth)
• MCP server · Discovery · Supported chains
• Integrations — drop PipRail into agent frameworks: OpenClaw, Hermes, elizaOS, n8n & Mastra (more coming)
• Runnable examples — merchant + agent demos, a live Anvil end-to-end, and the why-402 teardown
• Releasing (tag-driven CI) · Contributing (DCO)

Spread the word

PipRail is free, open-source, and has no backend to sell you — so word of mouth is how it grows. If it saved you from building a payments backend, the best way to give back is to help other developers (and their agents) find it:

• ⭐ Star PipRail on GitHub — the #1 way to help others discover it
• 𝕏 Follow @piprailhq — new chains, ship logs, and agent-payment tips
• 🌐 piprail.com · 📖 docs.piprail.com

License & trademark

Code: MIT — use it, fork it, ship it, commercially or otherwise.

Name & brand: PipRail™, the logo, and the @piprail npm scope are trademarks of the PipRail project — MIT covers the code, not the name. Build on it freely; just don't call a fork "PipRail" or imply it's official. See TRADEMARK.md.

_{Built for the agent economy · <a href="https://piprail.com">piprail.com</a>}