MCP Installer

Installs MCP servers published to npm registries by invoking npx with the package name, automatically resolving dependencies and downloading binaries. The system parses the package name, constructs an npx command with optional arguments and environment variables, executes it in a subprocess, and streams output back to Claude. This approach leverages npm's existing package resolution and caching mechanisms rather than implementing custom dependency management.

Installs MCP servers published to PyPI by invoking the `uv` package manager (a fast Rust-based Python package installer) with the package name, handling Python dependency resolution and virtual environment setup. The system constructs a uv command with optional arguments and environment variables, executes it as a subprocess, and registers the installed server in Claude Desktop's configuration. This approach uses uv instead of pip for faster, more reliable dependency resolution.

Installs MCP servers from local directories on the user's machine by reading the server's package.json or pyproject.toml, validating the directory structure, and registering it in Claude Desktop's configuration without downloading or copying files. The system locates the configuration file based on OS, parses the existing MCP server list, appends the new local server entry with its command and arguments, and writes the updated config back. This approach enables development workflows where users test MCP servers before publishing to registries.

Automatically locates and updates Claude Desktop's configuration file across Windows, macOS, and Linux by detecting the operating system and constructing the correct path to the MCP server configuration JSON. The system reads the existing configuration, parses the MCP server list, appends or updates the new server entry with its command, arguments, and environment variables, and writes the updated JSON back with proper formatting. This abstraction eliminates manual config file editing and handles OS-specific path differences transparently.

Passes custom command-line arguments and environment variables to MCP servers during installation, enabling servers to be configured with startup parameters (ports, data directories) and credentials (API keys, tokens) without requiring post-installation manual configuration. The system accepts optional arguments array and environment variables object, constructs the appropriate command (npx, uv, or local) with these parameters, executes the server startup, and registers the configured server in Claude Desktop. This approach enables parameterized server installation workflows.

Parses natural language requests from Claude to extract MCP server name, installation source (npm, PyPI, or local path), optional arguments, and environment variables, then validates that the request contains sufficient information to proceed with installation. The system uses Claude's tool schema to define expected input parameters (server name, source type, args, env), validates that required fields are present, and routes the request to the appropriate installation handler (npm, PyPI, or local). This abstraction enables Claude to understand and execute installation requests in natural language.

Executes package manager commands (npx, uv) and local server startup as subprocesses, streams their output back to Claude in real-time, and captures exit codes and error messages for error reporting. The system spawns a child process with the constructed command, pipes stdout/stderr to the MCP response stream, monitors the process for completion, and returns the exit code and final status. This approach enables users to see installation progress and diagnose failures without waiting for the entire operation to complete.