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Provides a dynamic MCP tool builder that creates new Python-based tools from natural language prompts and exposes them to MCP clients.
Configuration
View docs{
"mcpServers": {
"hanweg-mcp-tool-builder": {
"command": "uv",
"args": [
"--directory",
"PATH_TO\\\\mcp-tool-builder",
"run",
"tool-builder"
]
}
}
}You can use the MCP Tool Builder server to dynamically create new tools via MCP clients such as Claude Desktop. Tools are defined in natural language and saved as Python scriptlets, enabling your LLMs to extend their capabilities on demand.
To use this MCP server with a client like Claude Desktop, run the tool builder server and point your client to it. Tools you describe are stored as Python scriptlets and can be invoked by your LLM-powered workflows. New tool definitions are saved in the tools.json file and the actual tool code is saved under the tools folder.
Prerequisites you need before installing are Python and a suitable runtime shell. You also need a client environment capable of loading MCP servers.
# Step 1: Prepare and create a virtual environment for the MCP Tool Builder
cd mcp-tool-builder
uv venv
.venv\Scripts\activate
# Step 2: Install the tool builder in editable mode
uv pip install -e .Configure Claude Desktop to use the MCP Tool Builder by adding a server entry that runs the tool builder locally.
{
"mcpServers": {
"tool-builder": {
"command": "uv",
"args": [
"--directory",
"PATH_TO\\mcp-tool-builder",
"run",
"tool-builder"
]
}
}
}- The MCP Tool Builder saves new tools as Python scriptlets under the tools directory and saves their definitions in tools.json. You can create tools by describing them in Claude Desktop and then restart may be required for new tools to become active in some clients.
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