4q Tokenz MCP server

MCP Proxy Gateway

A context-aware MCP proxy that reduces token usage by exposing only 3 tools (mcpsearch, mcpcall, mcp_schema) to LLMs instead of the full catalog.

Why This Exists

When you connect multiple MCP servers to an LLM, every tool from every server is listed in the LLM's context window. For a typical workspace with 50-100 tools across multiple MCP servers, that's thousands of tokens of schema documentation on every request.

MCP Proxy Gateway sits between your LLM and your MCP servers, offering:

• JIT tool loading — tools from upstream servers are discovered once at startup, then tools are called on-demand. Clients never see the full catalog.
• Intelligent search — fast lexical (BM25) search to find the right tool for a query. Tool tokens are pre-computed at startup for zero-overhead per-query scoring.
• Token savings — LLMs only see 3 tool schemas (search, call, schema) instead of 50+. Typical savings: 20-40% per turn for tool-heavy workflows.
• Zero native dependencies — pure JavaScript, no native modules, no model downloads, no supply chain risk from ML packages.

┌─────────────────────────────────────────────────────────────────┐
│                         Your LLM                                │
│   (sees only: mcp_search, mcp_call, mcp_schema)                │
└────────────────────┬────────────────────────────────────────────┘
                     │
         ┌───────────▼──────────────┐
         │   MCP Proxy Gateway      │
         │ ┌──────────────────────┐ │
         │ │ Tool Registry        │ │
         │ │ (BM25 lexical)       │ │
         │ └──────────────────────┘ │
         │ ┌──────────────────────┐ │
         │ │ Connector Manager    │ │
         │ │ (Idle timeout reap)  │ │
         │ └──────────────────────┘ │
         └────────────┬─────────────┘
                      │
        ┌─────────────┼─────────────┐
        │             │             │
        ▼             ▼             ▼
   ┌─────────┐  ┌─────────┐  ┌─────────┐
   │Google   │  │MailerLite│ │Your Svc │
   │Gmail    │  │ Campaigns│ │ Custom  │
   │Calendar │  │          │ │ Tools   │
   │Drive    │  │          │ │         │
   └─────────┘  └─────────┘  └─────────┘

Prerequisites

• Node.js 18+ with npm or pnpm
• One or more MCP servers to proxy (stdio or HTTP)

Installation

From Source

git clone https://github.com/steveweltman/4q-tokenz.git
cd 4q-tokenz

pnpm install
pnpm build

# Install to ~/.local/bin and configure
./install.sh

As a Dependency

npm install -g 4q-tokenz

Getting Started: Google Workspace Example

Here's a concrete walkthrough to connect Google Workspace (Gmail, Calendar, Drive) to your LLM through the proxy:

Step 1: Choose or Build an MCP Server for Google

You need an MCP server that wraps Google APIs. Options:

• @antidrift/mcp-google (recommended) — A collection of MCP server implementations for Google Workspace (Gmail, Calendar, Drive, Docs, Sheets). Works out of the box with this proxy.

npm install @antidrift/mcp-google
  # or
  npx @antidrift/mcp-google --help

• @modelcontextprotocol/server-gmail — Gmail-only, official MCP server
• Build your own — See the MCP spec to wrap your own APIs

Step 2: Set Up Google OAuth

1. Go to Google Cloud Console
2. Create a new project or select an existing one
3. Enable these APIs:

• Gmail API
• Google Calendar API
• Google Drive API

1. Create an OAuth 2.0 credential (type: Desktop application)
2. Download the credential JSON
3. Run the Google MCP server once to generate token.json:

GOOGLE_CREDENTIAL_FILE=~/Downloads/credentials.json \
   npx @antidrift/mcp-google

This opens a browser for you to authorize. Once done, it saves token.json locally.

Step 3: Configure the Proxy

Create ~/.config/4q-tokens/config.json:

Shortened. The full README is on GitHub.