WORK IN PROGRESS - USE WITH CAUTION - Windows
LocalAbout WORK IN PROGRESS - USE WITH CAUTION - Windows
MCP Tool Builder is an MCP server that lets LLMs create new tools dynamically from natural language descriptions, for use in clients such as Claude Desktop. The project is marked as work in progress with Windows-specific setup notes, so it should be used with caution.
Key features
- 01Creates new tools from natural language descriptions
- 02Saves new tools as Python scriptlets
- 03Records tool definitions in a tools.json file
- 04Includes Bitcoin price and weather forecast example tools
- 05New tools require a client restart to load
Use cases
- 01Generating custom tools on demand in Claude Desktop
- 02Fetching the current Bitcoin price
- 03Retrieving weather forecasts for US ZIP codes
MCP support
This project is an MCP server that exposes a tool-creation capability to MCP clients such as Claude Desktop and loads newly generated tools after a restart.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
We haven’t collected a package or remote endpoint for this server. Follow the instructions in the project README.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEWORK IN PROGRESS - USE WITH CAUTION - Windows
MCP Tool Builder
An MCP server that empowers LLMs to dynamically create new tools through MCP clients such as Claude Desktop.
Features
- Create new tools by describing them in natural language
- Requires client restart to use new tools (Claude Desktop)
- New tools are saved as python scriptlets in ...\mcp-tool-builder\tools
- New tool definitions are saved in ...\mcp-tool-builder\tools\tools.json
Example tools included at installation
- get_bitcoin_price: Fetches current Bitcoin price from CoinGecko
- get_weather_forecast: Gets weather for US ZIP codes (uses geopy)
Creating New Tools
Use the create_tool command in Claude Desktop (or suggest strongly!!) to create new tools dynamically
Installation
- Clone this repository
- Install dependencies:
cd mcp-tool-builder
uv venv
.venv\Scripts\activate
uv pip install -e .
Usage with Claude Desktop
Add to claude_desktop_config.json:
{
"mcpServers": {
"tool-builder": {
"command": "uv",
"args": [
"--directory",
"PATH_TO\\mcp-tool-builder",
"run",
"tool-builder"
]
}
}
}
Comments
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