MCP Coordinator

# MCP Coordinator An MCP server that acts as a proxy for multiple MCP servers, exposing only 3 tools to Claude instead of loading all tool definitions from each server. This dramatically reduces context window consumption while maintaining full access to all MCP capabilities. ## The Problem Each MCP server you add to Claude loads all its tool definitions into your context window. GitHub MCP alone can consume 50+ tool definitions worth of tokens on every single message. ## The Solution The MCP Coordinator exposes only 3 tools. When Claude needs to use an MCP, the Coordinator dynamically loads it, calls the tool, and returns just the result. ## Features - Reduce context window usage from ~15,000+ tokens to ~500 tokens - Dynamically load MCP servers on-demand - Reuse connections for better performance - Easy manifest-based configuration for adding/removing servers - Support for environment variable substitution in server configs ## Tools ### list_mcps List all available MCP servers and their descriptions. **Inputs:** None **Returns:** Array of server names and descriptions from the manifest. ### get_mcp_tools Get the list of tools available in a specific MCP server. **Inputs:** - `server_name` (string, required): Name of the MCP server from `list_mcps` **Returns:** Array of tools with names, descriptions, and input schemas. ### call_mcp_tool Call a specific tool on an MCP server. **Inputs:** - `server_name` (string, required): Name of the MCP server - `tool_name` (string, required): Name of the tool to call - `tool_args` (object, optional): Arguments to pass to the tool **Returns:** The result from the MCP tool call. ## Usage The MCP Coordinator is designed for: - Reducing context window consumption when using multiple MCP servers - Projects that need access to many MCPs but not all at once - Workflows where you want to query available tools before using them - Keeping your Claude conversations lean and focused ## Configuration The coordinator itself requires **no API keys or tokens**. You only need to provide tokens for specific MCP servers in the manifest that require them (like GitHub MCP). ### Usage with Claude Desktop Add this to your `claude_desktop_config.json`: ```json { "mcpServers": { "coordinator": { "command": "node", "args": ["C:\\path\\to\\mcp_coordinator\\build\\index.js"] } } } ``` ### Usage with Claude Code #### Project-Level Configuration Create a `.mcp.json` file in your project root: ```json { "mcpServers": { "coordinator": { "command": "cmd", "args": ["/c", "node", "C:\\path\\to\\mcp_coordinator\\build\\index.js"] } } } ``` #### Global Configuration (All Projects) Create `~/.claude/.mcp.json`: ```json { "mcpServers": { "coordinator": { "command": "cmd", "args": ["/c", "node", "C:\\path\\to\\mcp_coordinator\\build\\index.js"] } } } ``` ### Passing Tokens for Specific MCPs If you use MCP servers that require authentication (like GitHub), pass the tokens as environment variables: ```json { "mcpServers": { "coordinator": { "command": "node", "args": ["C:\\path\\to\\mcp_coordinator\\build\\index.js"], "env": { "GITHUB_TOKEN": "your_github_token_here" } } } } ``` The coordinator passes these to child MCPs via the `${VAR_NAME}` syntax in the manifest. ## Adding MCP Servers Edit `src/manifest.json` (and rebuild) or directly edit `build/manifest.json`. ### MCPs That Need No Authentication Many MCPs work without any tokens: ```json { "servers": { "sequential-thinking": { "description": "Step-by-step thinking and problem decomposition", "command": "npx", "args": ["-y", "@modelcontextprotocol/server-sequential-thinking"], "env": {} }, "filesystem": { "description": "Read, write, and manage local files", "command": "npx", "args": ["-y", "@modelcontextprotocol/server-filesystem", "C:/"], "env": {} } } } ``` ### MCPs That Require Authentication Some MCPs need API tokens to access external services: ```json { "servers": { "github": { "description": "GitHub operations: repos, issues, PRs, branches, commits", "command": "npx", "args": ["-y", "@modelcontextprotocol/server-github"], "env": { "GITHUB_PERSONAL_ACCESS_TOKEN": "${GITHUB_TOKEN}" } } } } ``` Environment variables use `${VAR_NAME}` syntax and are resolved from the coordinator's environment at runtime. Only pass the tokens you actually need for the MCPs you're using. ## Building ```bash # Install dependencies npm install # Build TypeScript npm run build # Copy manifest to build folder cp src/manifest.json build/manifest.json ``` ## Context Window Savings | Approach | Tools in Context | Approximate Tokens | |----------|------------------|-------------------| | Direct GitHub MCP | 50+ tools | ~15,000 tokens | | Direct + Filesystem + Fetch | 80+ tools | ~25,000 tokens | | **MCP Coordinator** | 3 tools | ~500 tokens | ## Included Servers The default manifest includes: - **github** - GitHub operations (repos, issues, PRs, branches, commits) - **filesystem** - Read, write, and manage local files - **fetch** - Fetch URLs and retrieve web content ## Acknowledgments - Reddit user [u/mrgoonvn](https://reddit.com/user/mrgoonvn) for the inspiration regarding MCP context bloat that led to this project - [Anthropic](https://anthropic.com) for the [Model Context Protocol SDK](https://github.com/modelcontextprotocol/typescript-sdk) - The MCP community for the official server implementations (GitHub, Filesystem, Fetch, Sequential Thinking) - Built with [Claude Code](https://claude.ai/code) ## License This MCP server is licensed under the GPL-3.0 License. This means you are free to use, modify, and distribute the software, subject to the terms and conditions of the GPL-3.0 License. For more details, please see the LICENSE file in the project repository.