Skip to main content
Glama
pcandido

gtwmcp

by pcandido
OverviewSchemaSourceRelated ServersDiscussionsAdmin
JavaScript
Local

gtwmcp — MCP Gateway

CI npm version node license dependencies

A zero-dependency MCP gateway. Connect multiple AI harnesses to multiple MCP servers through a single, centrally-managed stdio interface. No overhead, no bloat — just the Node.js stdlib. Secrets stay in the OS keychain, never in config files.

Architecture

Install

npm install -g gtwmcp

Requires Node.js >= 22.

Related MCP server: mcp-client-credentials-auth

Quick Start

Add a stdio MCP server:

$ gtwmcp add github --type stdio --command npx --args "-y,@modelcontextprotocol/server-github" --description "GitHub MCP"
Server "github" added.

Add an SSE MCP server with OAuth:

$ gtwmcp add jira --type sse --url https://mcp.jira.example.com/sse --oauth --description "Jira MCP"
Server "jira" added.

List servers:

$ gtwmcp list
NAME    TYPE   STATUS       DESCRIPTION
------  -----  -----------  -----------
github  stdio  ✅ enabled   GitHub MCP
jira    sse    ✅ enabled   Jira MCP

Authenticate an OAuth server:

$ gtwmcp auth jira
[jira] https://mcp.jira.example.com/sse
  ✅ Token valid (expires in 45m)

$ gtwmcp auth --force          # re-authenticate all OAuth servers

List tools from a server:

$ gtwmcp get jira
jira (sse) — https://mcp.jira.example.com/sse
Listing tools...

  1. search_jira_issues: Search Jira issues using JQL
  2. get_jira_issue: Get a specific Jira issue

2 tools available.

CLI Reference

gtwmcp add    <name>    Add or update an MCP server
gtwmcp remove <name>    Remove an MCP server
gtwmcp get    <name>    List tools and descriptions from a server
gtwmcp list             List all servers with status
gtwmcp auth   [name]    Authenticate OAuth servers (--force to re-auth)
gtwmcp enable <name>    Enable a server
gtwmcp disable <name>   Disable a server
gtwmcp serve            Start the MCP gateway in stdio mode

Gateway

The gateway (gtwmcp serve) speaks MCP over stdio to the client. On startup it:

  1. Reads ~/.gtwmcp.json

  2. Connects to all enabled upstream servers in parallel

  3. Calls initialize and tools/list on each

  4. Prefixes every tool with the server name: <server>__<tool>

  5. Applies allow/block list filters

  6. Presents a single consolidated tool list

Gateway

Tool Filtering

Control which tools are exposed via environment variables:

Variable

Behavior

GTWMCP_ALLOW_LIST

Only matching tools pass

GTWMCP_BLOCK_LIST

All tools except matching pass

Both set

Allow first, then block removes from that subset

Neither set

All tools pass

Patterns support trailing * wildcard:

# Expose only read tools
GTWMCP_ALLOW_LIST="github__read_*,github__search_*,github__list_*"

# Expose everything except destructive tools
GTWMCP_BLOCK_LIST="github__delete_*,github__admin_*"

Configuration

~/.gtwmcp.json:

{
  "version": 1,
  "servers": {
    "github": {
      "type": "stdio",
      "enabled": true,
      "description": "GitHub MCP server",
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-github"],
      "env": {
        "GITHUB_PERSONAL_ACCESS_TOKEN": "ghp_xxxxxxxxxxxx"
      }
    },
    "jira": {
      "type": "sse",
      "enabled": true,
      "description": "Jira MCP",
      "url": "https://mcp.jira.example.com/sse",
      "headers": {
        "X-Custom-Header": "value"
      },
      "oauth": true
    }
  }
}

  • stdio: command, args, optional env and description

  • sse: url, optional headers, oauth, and description

  • "oauth": true means all OAuth data lives in the OS keychain (never in this file)

OAuth

The gateway supports Authorization Code Flow with PKCE for SSE servers.

OAuth Flow

At runtime, gtwmcp serve auto-refreshes expired tokens before each call.

Keychain

Platform

Backend

macOS

/usr/bin/security (Keychain)

Linux

secret-tool (libsecret)

Use with Claude Code

Point Claude Code's MCP config at the gateway:

{
  "mcpServers": {
    "gtwmcp": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "gtwmcp", "serve"]
    }
  }
}

All your upstream MCP tools appear prefixed and unified in Claude Code.

Development

npm install
npm run check   # syntax validation
npm test        # 57 tests

Zero external dependencies. Node.js 22+ stdlib only.

This server cannot be deployed

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Maintenance

ActivityInactive
ResponsivenessNo issues

Resources

Related MCP Connectors

Related MCP Servers

  • MCP Compact

    quan2005
    A
    license
    A
    quality
    C
    maintenance
    Aggregates multiple upstream MCP servers into a single stdio-only runtime with a compact surface exposing only invoke and read.
    2
    2
    MIT

  • MCP Gateway

    cociweb
    A
    license
    Not graded
    quality
    C
    maintenance
    Aggregates multiple upstream MCP servers (stdio, streamable-http, sse, websocket) behind a single streamable-HTTP endpoint with declarative configuration, namespacing, filtering, and auto-reload.
    MIT

  • mcp-gway

    deuriib
    A
    license
    Not graded
    quality
    A
    maintenance
    Enables aggregating multiple MCP servers behind a single HTTP/SSE endpoint, with Code Mode to reduce token usage and support for OAuth and sandboxed execution.
    MIT