redshift-mcp-cli

Bridge CLI that connects Claude Desktop (stdio) to a remote Redshift MCP HTTP server.

Problem: Claude Desktop doesn't yet support HTTP-based MCP servers directly.

Solution: This CLI acts as a bridge/proxy that:

1. Connects to Claude Desktop via stdio (JSON-RPC 2.0)
2. Proxies all requests to the remote HTTP MCP server
3. Returns responses back to Claude Desktop

Installation

No installation needed! Use npx directly:

npx redshift-mcp-cli

Usage

Required Arguments

You must provide both --api-key and --server-url:

npx redshift-mcp-cli \
  --api-key your-secure-api-key \
  --server-url http://your-mcp-server.com/mcp

Command Line Options

| Option | Alias | Description | Required | Default | |--------|-------|-------------|----------|---------| | --api-key | -k | API key for the MCP server | ✅ | - | | --server-url | - | URL of the HTTP MCP server | ✅ | - |

Integration with Claude Desktop

Add this to your claude_desktop_config.json:

{
  "mcpServers": {
    "redshift": {
      "command": "npx",
      "args": [
        "redshift-mcp-cli",
        "--api-key", "your-secure-api-key",
        "--server-url", "http://your-mcp-server.com/mcp"
      ],
      "env": {}
    }
  }
}

How It Works

┌─────────────────┐          ┌──────────────────────┐          ┌──────────────────┐
│                 │          │                      │          │                  │
│  Claude Desktop │ stdio    │  redshift-mcp-cli    │  HTTP    │  Redshift MCP    │
│                 │─────────▶│  (Bridge/Proxy)      │─────────▶│  HTTP Server     │
│                 │          │                      │          │                  │
└─────────────────┘          └──────────────────────┘          └──────────────────┘
     JSON-RPC 2.0                  Proxies requests                  API: /mcp
                                    with x-api-key

Request Flow:

1. Claude Desktop sends MCP request via stdio (JSON-RPC 2.0)
2. CLI receives the request
3. CLI forwards request to HTTP MCP server with API key header
4. HTTP MCP server processes the request
5. CLI receives response and sends it back to Claude Desktop via stdio

Supported MCP Methods:

• initialize - Initialize the connection
• tools/list - List available tools
• tools/call - Execute a tool (e.g., execute_sql, analyze_table, get_execution_plan)
• resources/list - List available resources
• resources/read - Read a specific resource
• Notifications: initialized, cancelled, list_changed

Examples

Example 1: Basic Usage

npx redshift-mcp-cli \
  --api-key "abc123xyz789" \
  --server-url "http://your-mcp-server.com/mcp"

Example 2: Short Form

npx redshift-mcp-cli \
  -k "my-api-key" \
  --server-url "http://your-mcp-server.com/mcp"

Example 3: Custom Server URL

npx redshift-mcp-cli \
  --api-key "your-api-key" \
  --server-url "http://your-custom-server.com/mcp"

Example 4: Claude Desktop Configuration

{
  "mcpServers": {
    "redshift": {
      "command": "npx",
      "args": [
        "redshift-mcp-cli",
        "--api-key", "your-api-key-here",
        "--server-url", "http://your-mcp-server.com/mcp"
      ]
    }
  }
}

Features

• ✅ Bridges Claude Desktop (stdio) to HTTP MCP servers
• ✅ API key authentication via x-api-key header
• ✅ Full JSON-RPC 2.0 support
• ✅ No installation required (uses npx)
• ✅ Supports all MCP methods: tools, resources, and notifications
• ✅ Both server URL and API key required from CLI args

Troubleshooting

Missing Required Arguments

If you don't provide both --api-key and --server-url, you'll get an error:

Error: API key is required
Error: Server URL is required

Make sure to provide both arguments.

Connection Refused

If you get "connection refused", check:

1. The MCP server URL is correct and accessible
2. The server is running and accepting connections
3. Any firewalls allow the connection

Authentication Failed

Verify your API key:

1. Check the API key is correct
2. Ensure the MCP server accepts the key
3. The API key is sent via x-api-key header

Port Already in Use

This shouldn't happen as the CLI doesn't bind to any port - it only connects via HTTP. If you see this error, check if another instance is running.

No Response

The CLI logs to stderr. Check Claude Desktop logs or run the CLI manually to see error messages.

Technical Details

Protocol Translation

The CLI translates between two transports:

Claude Desktop → CLI (stdio):

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/list"
}

CLI → HTTP MCP Server:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/list"
}

Headers: x-api-key: your-key

Response Translation works the same way back.

Security Notes

• API keys are sent via x-api-key header to the HTTP MCP server
• The CLI itself doesn't store or log API keys (only shows first 8 chars)
• All communication between CLI and MCP server should use HTTPS in production
• The CLI acts as a transparent proxy - no data is modified

License

MIT