bun-fun

Simple local stdio MCP server example compiled with Bun

Install dependencies

bun install

Build executable

bun run build

Add to Claude Desktop

Executable:

{
  ...
  "mcpServers": {
    "example-mcp-server": {
      "command": "<path-to-executable>"
    }
  }
}

Development:

{
  ...
  "mcpServers": {
    "example-mcp-server-dev": {
      "command": "bun",
      "args": ["run", "<path-to-index.ts>"]
    }
  }
}

Windows

• Config: %APPDATA%\Claude\claude_desktop_config.json
• Executable: C:\\path\\to\\bun-fun\\mcp-server.exe
• Development: C:\\path\\to\\bun-fun\\index.ts

macOS

• Config: ~/Library/Application Support/Claude/claude_desktop_config.json
• Executable: /path/to/bun-fun/mcp-server
• Development: /path/to/bun-fun/index.ts

Add to Claude Code

CLI

Executable:

claude mcp add example-mcp-server "<path-to-executable>"

Development:

claude mcp add example-mcp-server-dev "bun" --args "run" "<path-to-index.ts>"

Windows

• Executable: C:\\path\\to\\bun-fun\\mcp-server.exe
• Development: C:\\path\\to\\bun-fun\\index.ts

macOS/Linux

• Executable: /path/to/bun-fun/mcp-server
• Development: /path/to/bun-fun/index.ts

From Claude Desktop

[!NOTE] macOS and WSL only.

claude mcp add-from-claude-desktop

To-do

• [ ] IDE examples

Available MCP Tools

This server provides the following MCP tools:

get_current_time

Returns the current time in ISO format.

Parameters: None

Example response: 2025-09-20T15:30:45.123Z

echo

Echoes back the provided message.

Parameters:

• message (string, required): The message to echo back

Example:

• Input: { "message": "Hello, world!" }
• Output: Echo: Hello, world!

add_numbers

Adds two numbers together.

Parameters:

• a (number, required): First number
• b (number, required): Second number

Example:

• Input: { "a": 5, "b": 3 }
• Output: 5 + 3 = 8