PipRail MCP Server

Q: How do I install the PipRail MCP server in Claude Code?

Run: claude mcp add piprail -e PIPRAIL_PRIVATE_KEY=' ' -- npx -y @piprail/mcp. For Cursor, VS Code, Claude Desktop and Windsurf, use the install tabs above.

by piprailio.github.piprail/mcpv0.10.0

PipRail MCP server — hand any MCP client a budget-bound x402 payment wallet. Local-only, no backend, no custody; the spend policy is enforced before any on-chain send, so the model literally cannot overspend.

9Node.jsstdioofficial registry

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Active30d ago

Install PipRail MCP server

claude mcp add piprail -e PIPRAIL_PRIVATE_KEY='<piprail-private-key>' -- npx -y @piprail/mcp

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": [
        "-y",
        "@piprail/mcp"
      ],
      "env": {
        "PIPRAIL_PRIVATE_KEY": "<piprail-private-key>"
      }
    }
  }
}

Add to ~/.cursor/mcp.json (global) or .cursor/mcp.json (project).

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": [
        "-y",
        "@piprail/mcp"
      ],
      "env": {
        "PIPRAIL_PRIVATE_KEY": "<piprail-private-key>"
      }
    }
  }
}

Settings → Developer → Edit Config (claude_desktop_config.json), then restart.

{
  "servers": {
    "piprail": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@piprail/mcp"
      ],
      "env": {
        "PIPRAIL_PRIVATE_KEY": "<piprail-private-key>"
      }
    }
  }
}

Add to .vscode/mcp.json in your workspace.

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": [
        "-y",
        "@piprail/mcp"
      ],
      "env": {
        "PIPRAIL_PRIVATE_KEY": "<piprail-private-key>"
      }
    }
  }
}

Add to ~/.codeium/windsurf/mcp_config.json.

Configuration

Variable	Required	Secret	Description
PIPRAIL_PRIVATE_KEY	—	yes	Your wallet's private key/seed for the chosen chain. Optional: omit it to run read-only (discover/quote/register/budget/guide); set it to let the agent pay. Stays on your machine; the spend policy caps every payment.
PIPRAIL_CHAIN	—	—	Chain to pay on (default: base).
PIPRAIL_CHAINS	—	—	Pay across several chains (instead of PIPRAIL_CHAIN): a comma-separated list, e.g. base,polygon,solana. Give each its own PIPRAIL_<CHAIN>_KEY (+ optional PIPRAIL_<CHAIN>_RPC_URL). The agent pays whichever chain a 402 asks for — the first listed that can settle — under one shared budget.
PIPRAIL_MAX_AMOUNT	—	—	Max spend per single payment, in token units (default: 0.10).
PIPRAIL_MAX_TOTAL	—	—	Lifetime spend cap per token, in token units (default: 10.00).
PIPRAIL_MAX_TOTAL_DENOM	—	—	Cross-token GRAND TOTAL: one spend cap per denomination across every stablecoin and chain, e.g. USD:20.00,EUR:5.00. Not a price oracle — sums tokens of the same unit, each counted 1:1. Native coins are excluded.
PIPRAIL_MAX_PAYMENTS	—	—	Lifetime cap on the NUMBER of payments, across every chain + token (e.g. 100).
PIPRAIL_MAX_PAYMENTS_PER_WINDOW	—	—	Cap on the number of payments within PIPRAIL_WINDOW_SECONDS (a rolling rate limit; set PIPRAIL_WINDOW_SECONDS too).
PIPRAIL_WARN_AT_FRACTION	—	—	Emit an early-warning event when spend crosses this fraction of any cap, e.g. 0.8 (80%). Needs PIPRAIL_EVENT_LOG to be visible.
PIPRAIL_SPEND_LOG	—	—	Path to a local append-only spend log. When set, the budget (lifetime, grand total, counts) SURVIVES a restart — hydrated from this file. No backend; you own the file.
PIPRAIL_EVENT_LOG	—	—	Mirror payment events (settled / declined / budget-threshold) as one-line JSON to 'stderr' or a file path — the operator's notification stream. Default: off.
PIPRAIL_TOKENS	—	—	Comma-separated allowed token symbols, plus the alias 'native' for the chain's coin (default: USDC).
PIPRAIL_SCHEMES	—	—	Comma-separated payment schemes to settle (default: onchain-proof). Add 'exact' (onchain-proof,exact) to also pay standard x402 servers GASLESS on EVM + Solana (method auto-selected). Add 'upto' to also pay metered x402 servers on EVM (Permit2): sign a MAX, the server settles the actual <= max.

Freshness

Active — last maintenance signal 30d ago. The newest of the signals below sets the band.

Last commit (default branch)
2026-09-10 · 30d ago · GitHub
Latest release
2026-09-10 · 30d ago · GitHub · sdk-v3.3.0
Package published
no data · npm/PyPI
Registry entry updated
2026-09-09 · 31d ago · official registry · v0.10.0

FAQ

›How do I install the PipRail MCP server in Claude Code?

Run: claude mcp add piprail -e PIPRAIL_PRIVATE_KEY='<piprail-private-key>' -- npx -y @piprail/mcp. For Cursor, VS Code, Claude Desktop and Windsurf, use the install tabs above.

›Does PipRail require an API key?

Yes. It expects PIPRAIL_PRIVATE_KEY, of which 1 is a secret.

›Can I use PipRail as a remote (hosted) MCP server?

No hosted endpoint is published; it runs locally over stdio.

›Is PipRail in the official MCP registry?

Yes, as io.github.piprail/mcp.