Party Time MCP Server

A simple MCP server that responds with "It's Party Time" when asked about the current time.

Overview

This is a simple implementation of an MCP server that directly reads from stdin and writes to stdout. It registers a single tool called get-time and always responds with "It's Party Time" when the tool is called.

The server implements the MCP protocol directly, handling JSON-RPC messages and responding appropriately.

Installation Instructions for macOS

1. Build the Executable

First, build the executable:

mix deps.get
mix escript.build

This will create an executable named party_time_mcp in your project directory.

Make sure it has execute permissions:

chmod +x ./party_time_mcp

2. Configure Claude Desktop

1. Open your Claude Desktop configuration file:

open -e ~/Library/Application\ Support/Claude/claude_desktop_config.json

2. Add the following to your configuration (if the file doesn't exist yet, create it with this content):

{
  "mcpServers": {
    "partytime": {
      "command": "/path/to/your/party_time_mcp",
      "args": []
    }
  }
}

Replace /path/to/your/party_time_mcp with the actual path to your executable.

3. Save the file and restart Claude Desktop

3. Testing Your Server

1. Open Claude Desktop
2. Ask Claude "What time is it?"
3. Claude should detect your tool and respond with "It's Party Time"

Troubleshooting

- Claude Desktop not finding the tool: Make sure the path in your configuration is correct and that the file has execute permissions
- Permissions issues: You might need to run chmod +x ./party_time_mcp if the executable doesn't have the right permissions
- Configuration file issues: Make sure your JSON is valid and properly formatted
- Claude Desktop restart: Ensure you've restarted Claude Desktop after making configuration changes
- JSON parsing errors: If you see errors like "Unexpected end of JSON input" or "Unexpected non-whitespace character after JSON":
- This is likely because the server is outputting additional text to stdout along with the JSON responses
- Make sure you're using the latest version of the server which fixes this issue by sending logs to stderr instead of stdout
- The server now ensures that only clean, properly formatted JSON is sent to stdout
- If you're still seeing these errors, check the Claude Desktop logs for more details
- Mix.env() error: If you see an error like function Mix.env/0 is undefined, this means the executable was built incorrectly. The Mix module is not available at runtime in an escript. Rebuild the executable with the latest code that fixes this issue.

Debugging

If you're experiencing JSON errors, you can run the server manually to see its output:

./party_time_mcp

Then in another terminal, you can send test JSON-RPC messages to it:

echo '{"jsonrpc":"2.0","id":"test-1","method":"tools/list"}' | ./party_time_mcp

You can also test other message types:

```bash