Client setup

Introduction

Every MCP client runs the server the same way: it spawns npx -y @piprail/mcp over stdio and hands it configuration through an env block. What differs per client is only where the config file lives, the top-level JSON key, and whether you can interpolate ${env:…} rather than pasting the raw key.

This page is one row per client. For what goes inside env, see Configuration; for the wallet key format your chain expects, see Wallets by family.

The invocation is identical everywhere

command and args never change — only the config wrapper around them does:

{
  "command": "npx",
  "args": ["-y", "@piprail/mcp"],
  "env": { "PIPRAIL_PRIVATE_KEY": "0xYOUR_PRIVATE_KEY", "PIPRAIL_CHAIN": "base" }
}

Clients at a glance

Client	Config file	Top-level key	`${env:…}`
Claude Desktop	`~/Library/Application Support/Claude/claude_desktop_config.json` (macOS) · `%APPDATA%\Claude\claude_desktop_config.json` (Windows)	`mcpServers`	No — file is a secret
Cursor	`.cursor/mcp.json` (project) · `~/.cursor/mcp.json` (global)	`mcpServers`	Yes
Claude Code	`.mcp.json` (project) · `~/.claude.json` (user)	`mcpServers`	Yes
Windsurf	`~/.codeium/windsurf/mcp_config.json`	`mcpServers`	Yes
VS Code (Copilot)	`.vscode/mcp.json`	`servers`	Yes
Cline	`cline_mcp_settings.json` (edited from the MCP Servers panel)	`mcpServers`	Yes

Claude Desktop

Open Settings → Developer → Edit Config, or edit the file directly. Claude Desktop does not interpolate ${env:…}, so the key goes in the file — keep it out of version control.

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": ["-y", "@piprail/mcp"],
      "env": {
        "PIPRAIL_PRIVATE_KEY": "0xYOUR_PRIVATE_KEY",
        "PIPRAIL_CHAIN": "base",
        "PIPRAIL_MAX_AMOUNT": "0.10",
        "PIPRAIL_MAX_TOTAL": "10.00",
        "PIPRAIL_TOKENS": "USDC"
      }
    }
  }
}

Restart Claude Desktop and the piprail_* tools appear.

Cursor

Project config at .cursor/mcp.json, or global at ~/.cursor/mcp.json. Cursor interpolates ${env:…}, so export the key to your shell and reference it:

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": ["-y", "@piprail/mcp"],
      "env": { "PIPRAIL_PRIVATE_KEY": "${env:PIPRAIL_PRIVATE_KEY}", "PIPRAIL_CHAIN": "base" }
    }
  }
}

Claude Code

Project config at .mcp.json (commit-safe with ${env:…}); user config across all projects lives in ~/.claude.json. Same shape, same ${env:…} support. You can also add it from the CLI — claude mcp add piprail --scope user --env PIPRAIL_CHAIN=base -- npx -y @piprail/mcp — which writes the same block for you.

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": ["-y", "@piprail/mcp"],
      "env": { "PIPRAIL_PRIVATE_KEY": "${env:PIPRAIL_PRIVATE_KEY}", "PIPRAIL_CHAIN": "base" }
    }
  }
}

Windsurf

Config at ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": ["-y", "@piprail/mcp"],
      "env": { "PIPRAIL_PRIVATE_KEY": "${env:PIPRAIL_PRIVATE_KEY}", "PIPRAIL_CHAIN": "base" }
    }
  }
}

VS Code (Copilot)

Config at .vscode/mcp.json. Note the top-level key is servers, not mcpServers:

{
  "servers": {
    "piprail": {
      "command": "npx",
      "args": ["-y", "@piprail/mcp"],
      "env": { "PIPRAIL_PRIVATE_KEY": "${env:PIPRAIL_PRIVATE_KEY}", "PIPRAIL_CHAIN": "base" }
    }
  }
}

Cline

Cline stores servers in cline_mcp_settings.json. Open it from the MCP Servers icon → Configure → Configure MCP Servers, then add the same mcpServers block:

{
  "mcpServers": {
    "piprail": {
      "command": "npx",
      "args": ["-y", "@piprail/mcp"],
      "env": { "PIPRAIL_PRIVATE_KEY": "${env:PIPRAIL_PRIVATE_KEY}", "PIPRAIL_CHAIN": "base" }
    }
  }
}

More than one chain

Each server instance is one wallet on one chain. To give an agent several rails, register the server once per chain — each entry is namespaced, so the agent gets all of them:

{
  "mcpServers": {
    "piprail-base": {
      "command": "npx", "args": ["-y", "@piprail/mcp"],
      "env": { "PIPRAIL_PRIVATE_KEY": "0xYOUR_EVM_KEY", "PIPRAIL_CHAIN": "base" }
    },
    "piprail-solana": {
      "command": "npx", "args": ["-y", "@piprail/mcp"],
      "env": { "PIPRAIL_PRIVATE_KEY": "YOUR_SOLANA_SECRET_BASE58", "PIPRAIL_CHAIN": "solana" }
    }
  }
}