FastDomainCheck MCP server

FastDomainCheck MCP Server allows you to check domain name registration status in bulk through a Model Context Protocol implementation, enabling secure two-way connections between AI tools (like Claude) and domain availability data.

Installation

Download and Setup

1. Download the binary file from the release page.

2. For Mac/Linux users, make the file executable:

   chmod +x FastDomainCheck-MCP-Server
   

Configure with Claude Desktop

Modify your claude-desktop-config.json file to include the FastDomainCheck MCP Server:

For Mac/Linux:

{
  "mcpServers": {
    "fastdomaincheck": {
      "command": "/path/to/FastDomainCheck-MCP-Server",
      "args": []
    }
  }
}

For Windows:

{
  "mcpServers": {
    "fastdomaincheck": {
      "command": "path/to/FastDomainCheck-MCP-Server.exe",
      "args": []
    }
  }
}

Python Version

Alternatively, you can use the Python version of this tool:

{
  "mcpServers": {
    "fastdomaincheck": {
      "command": "uvx",
      "args": [
        "fastdomaincheck-mcp-server"
      ]
    }
  }
}

The Python package is available at fastdomaincheck-mcp-server.

Usage

Checking Domain Registration Status

The server provides a single tool called check_domains that accepts a list of domains and returns their registration status.

Input Format

{
  "domains": ["example.com", "test.com"]
}

Parameters:

• domains: Array of domain names to check (maximum 50 domains per request)
  • Each domain must be less than 255 characters
  • No empty domain names allowed

Output Format

{
  "results": {
    "example.com": {
      "registered": true
    },
    "test.com": {
      "registered": false
    }
  }
}

Response Fields:

• results: Object with domain names as keys and check results as values
  • registered: Boolean indicating if the domain is registered (true) or available (false)

Example Usage

Request:

{
  "domains": ["example.com", "test123456.com"]
}

Response:

{
  "results": {
    "example.com": {
      "registered": true
    },
    "test123456.com": {
      "registered": false
    }
  }
}

Performance and Error Handling

Performance Considerations

• Domain checks run sequentially, taking approximately 0.3-1 second per domain
• Maximum 50 domains per request to prevent resource exhaustion
• WHOIS query timeout set to 10 seconds
• DNS query fallback when WHOIS query fails

Error Responses

The tool will return an error in these cases:

1. Empty domains list
2. More than 50 domains in request
3. Empty domain name
4. Domain name exceeding 255 characters
5. Result serialization failure

Error responses use this format:

{
  "error": "Error: domains list cannot be empty"
}

Features

• Bulk domain registration status checking
• Dual verification using WHOIS and DNS
• Support for IDN (Internationalized Domain Names)
• Concise output format
• Built-in input validation and error handling

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "fastdomaincheck" '{"command":"uvx","args":["fastdomaincheck-mcp-server"]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "fastdomaincheck": {
            "command": "uvx",
            "args": [
                "fastdomaincheck-mcp-server"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "fastdomaincheck": {
            "command": "uvx",
            "args": [
                "fastdomaincheck-mcp-server"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect