PipRail

{
  "$schema": "https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json",
  "name": "io.github.piprail/mcp",
  "description": "Budget-bound x402 payment wallet for AI agents — pays HTTP 402 URLs, capped locally. No backend.",
  "title": "PipRail",
  "repository": {
    "url": "https://github.com/piprail/piprail",
    "source": "github",
    "subfolder": "mcp"
  },
  "version": "0.10.0",
  "websiteUrl": "https://piprail.com/mcp",
  "packages": [
    {
      "registryType": "npm",
      "identifier": "@piprail/mcp",
      "version": "0.10.0",
      "transport": {
        "type": "stdio"
      },
      "environmentVariables": [
        {
          "description": "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.",
          "format": "string",
          "isSecret": true,
          "name": "PIPRAIL_PRIVATE_KEY"
        },
        {
          "description": "Chain to pay on (default: base).",
          "format": "string",
          "name": "PIPRAIL_CHAIN"
        },
        {
          "description": "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.",
          "format": "string",
          "name": "PIPRAIL_CHAINS"
        },
        {
          "description": "Max spend per single payment, in token units (default: 0.10).",
          "format": "string",
          "name": "PIPRAIL_MAX_AMOUNT"
        },
        {
          "description": "Lifetime spend cap per token, in token units (default: 10.00).",
          "format": "string",
          "name": "PIPRAIL_MAX_TOTAL"
        },
        {
          "description": "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.",
          "format": "string",
          "name": "PIPRAIL_MAX_TOTAL_DENOM"
        },
        {
          "description": "Lifetime cap on the NUMBER of payments, across every chain + token (e.g. 100).",
          "format": "string",
          "name": "PIPRAIL_MAX_PAYMENTS"
        },
        {
          "description": "Cap on the number of payments within PIPRAIL_WINDOW_SECONDS (a rolling rate limit; set PIPRAIL_WINDOW_SECONDS too).",
          "format": "string",
          "name": "PIPRAIL_MAX_PAYMENTS_PER_WINDOW"
        },
        {
          "description": "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.",
          "format": "string",
          "name": "PIPRAIL_WARN_AT_FRACTION"
        },
        {
          "description": "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.",
          "format": "string",
          "name": "PIPRAIL_SPEND_LOG"
        },
        {
          "description": "Mirror payment events (settled / declined / budget-threshold) as one-line JSON to 'stderr' or a file path — the operator's notification stream. Default: off.",
          "format": "string",
          "name": "PIPRAIL_EVENT_LOG"
        },
        {
          "description": "Comma-separated allowed token symbols, plus the alias 'native' for the chain's coin (default: USDC).",
          "format": "string",
          "name": "PIPRAIL_TOKENS"
        },
        {
          "description": "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.",
          "format": "string",
          "name": "PIPRAIL_SCHEMES"
        }
      ]
    }
  ]
}