WhatsApp‑MCP (Go Edition)

A lightweight, WhatsApp MCP server and bridge — rewritten entirely in Go for simplicity, portability, and real‑world automation workflows.

This project is a re‑imagining of the original whatsapp-mcp by lharries, who created the first WhatsApp MCP bridge using a Python MCP server and a Go WhatsApp client powered by WhatsMeow. Their work demonstrated how Claude Desktop could interact with WhatsApp through the MCP protocol, and this project would not exist without that foundation.

Start whatsapp-bridge -> then run whatsapp-mcp-server in your preferred mode (STDIO or HTTP).

Installation

Prerequisites

• Go
• Anthropic Claude Desktop app (or Cursor) or n8n workflow
• FFmpeg (optional) - Only needed for audio messages. If you want to send audio files as playable WhatsApp voice messages, they must be in .ogg Opus format. With FFmpeg installed, the MCP server will automatically convert non-Opus audio files. Without FFmpeg, you can still send raw audio files using the send_file tool.

Steps

1. Clone this repository

   git clone https://github.com/iamatulsingh/whatsapp-mcp-go.git
   cd whatsapp-mcp-go
   

2. Run the WhatsApp bridge Navigate to the whatsapp-bridge directory and run the Go application:

   cd whatsapp-bridge
   go run main.go
   

   The first time you run it, you will be prompted to scan a QR code. Scan the QR code with your WhatsApp mobile app to authenticate. After approximately 20 days, you will might need to re-authenticate.

   3. Connect to the MCP server

      cd whatsapp-mcp-server
      go build -o whatsapp-mcp
      

      Copy the below json with the appropriate {{PROJECT_BASE_PATH}} value:

      {
           "mcpServers": {
               "whatsapp-mcp": {
                  "command": "{{PROJECT_BASE_PATH}}/whatsapp-mcp-server/whatsapp-mcp",
                  "env": {
                       "WHATSAPP_API_KEY": "c3VwZXItbG9uZy1yYW5kb20tc3RyaW5nLW1pbmltdW0tb2YtNjQtY2hhcmFjdGVycy15b3UtbmVlZC10by1wYXN0ZS1oZXJl"
                  }
               }
           },
           "preferences": {
               "sidebarMode": "chat",
               "coworkScheduledTasksEnabled": false
           }
       }
      

      For Claude, save this as claude_desktop_config.json in your Claude Desktop configuration directory at:

      ~/Library/Application Support/Claude/claude_desktop_config.json
      

      For Cursor, save this as mcp.json in your Cursor configuration directory at:

      ~/.cursor/mcp.json
      

Windows Compatibility

If you're running this project on Windows, be aware that go-sqlite3 requires CGO to be enabled in order to compile and work properly. By default, CGO is disabled on Windows, so you need to explicitly enable it and have a C compiler installed.

Steps to get it working:

1. Install a C compiler
   We recommend using MSYS2 to install a C compiler for Windows. After installing MSYS2, make sure to add the ucrt64\bin folder to your PATH.
   → A step-by-step guide is available here.

2. Enable CGO and run the app

   cd whatsapp-bridge
   go env -w CGO_ENABLED=1
   go run main.go # or use this to enabled webhook and http streaming, `WEBHOOK_URL=http://192.168.178.119:5777/sse IS_HTTP=true go run main.go`
   

Or run everything in Docker

The repo ships a docker-compose.yaml at the root that brings up three services: postgres, wa-bridge, and wa-mcp. The MCP server is started in HTTP mode (port 5777) because that is the only mode that fits a long-running container — see "MCP server: stdio vs HTTP" below for when to use each.

# 1. Set the four required vars (in .env at repo root, or in your shell)
cat > .env <<EOF
WHATSAPP_API_KEY=$(openssl rand -base64 48)
WHATSAPP_JWT_SECRET=$(openssl rand -base64 48)
POSTGRES_USER=whatsapp
POSTGRES_PASS=$(openssl rand -base64 24)
EOF

# 2. Bring it all up
docker compose up

Once running:

• Bridge REST API: http://localhost:8080/api/... (after /auth/login)
• MCP HTTP endpoint: http://localhost:5777

MCP server: stdio vs HTTP

The MCP server has two run modes selected by IS_HTTP:

Mode	When to use	How to launch
stdio (IS_HTTP=false, default)	Claude Desktop, Cursor, or any host that spawns the MCP server as a child process	go build a local binary; reference it from claude_desktop_config.json / mcp.json (see below)
HTTP (IS_HTTP=true)	n8n, web automation, or any client connecting over the network	docker compose up — the wa-mcp service runs in HTTP mode by default, listening on :5777

Stdio mode is not appropriate for the Docker image — Claude Desktop does not natively docker run to spawn an MCP child. Build a local binary instead.

Authentication

The HTTP API is protected by a two-step API key → JWT flow.

1. Send your static API key to /auth/login once. The bridge returns a 45-minute JWT.
2. Use the JWT as Authorization: Bearer <jwt> on every /api/... call.

Step 1: Get a JWT

curl -X POST \
  -H "Authorization: Bearer $WHATSAPP_API_KEY" \
  http://localhost:8080/auth/login
# {"token":"eyJhbGciOiJIUzI1NiIs..."}

Step 2: Call the API

TOKEN=eyJhbGciOiJIUzI1NiIs...
curl -H "Authorization: Bearer $TOKEN" http://localhost:8080/api/chats

The MCP server does this automatically: configure WHATSAPP_API_KEY and it fetches/refreshes JWTs as needed.

Rate limiting

/auth/login is rate-limited per client IP (default: 5 attempts / minute). Override with AUTH_LOGIN_RATE=<count>/<window> (e.g. 10/30s). Behind a reverse proxy, terminate rate limiting upstream — the bridge currently uses r.RemoteAddr and does not consult X-Forwarded-For.

Architecture Overview

This application consists of two main components:

1. WhatsApp Bridge (whatsapp-bridge/): A Go application that connects to WhatsApp's web API, handles authentication via QR code, and stores message history in SQLite. It serves as the bridge between WhatsApp and the MCP server.

2. MCP Server (whatsapp-mcp-server/): A Go implemention of the Model Context Protocol (MCP), which provides standardized tools for Claude to interact with WhatsApp data and send/receive messages.

Data Storage

• All message history is stored in postgres by default and you'll need to create a database name whatsapp OR a SQLite database within the whatsapp-bridge/store/ directory
• The database maintains tables for chats and messages
• Messages are indexed for efficient searching and retrieval

MCP Tools

Claude can access the following tools to interact with WhatsApp:

• search_contacts: Search for contacts by name or phone number
• list_messages: Retrieve messages with optional filters and context
• list_chats: List available chats with metadata
• get_chat: Get information about a specific chat
• get_direct_chat_by_contact: Find a direct chat with a specific contact
• get_contact_chats: List all chats involving a specific contact
• get_last_interaction: Get the most recent message with a contact
• get_message_context: Retrieve context around a specific message
• send_message: Send a WhatsApp message to a specified phone number or group JID
• send_file: Send a file (image, video, raw audio, document) to a specified recipient
• send_audio_message: Send an audio file as a WhatsApp voice message (requires the file to be an .ogg opus file or ffmpeg must be installed)
• download_media: Download media from a WhatsApp message and get the local file path
• get_login_status: Check whether the bridge is connected and logged in to WhatsApp. Returns {connected, logged_in, pairing_required}.
• get_pairing_qr: Fetch the WhatsApp pairing QR as a PNG image. Returns image content when pairing is required, or a text message when the bridge is already logged in. Useful for completing the initial device-link flow from inside an MCP-aware UI instead of from the terminal.

Media Handling Features

The MCP server supports both sending and receiving various media types:

Media Sending

You can send various media types to your WhatsApp contacts:

• Images, Videos, Documents: Use the send_file tool to share any supported media type.
• Voice Messages: Use the send_audio_message tool to send audio files as playable WhatsApp voice messages.
  • For optimal compatibility, audio files should be in .ogg Opus format.
  • With FFmpeg installed, the system will automatically convert other audio formats (MP3, WAV, etc.) to the required format.
  • Without FFmpeg, you can still send raw audio files using the send_file tool, but they won't appear as playable voice messages.

Media Downloading

By default, just the metadata of the media is stored in the local database. The message will indicate that media was sent. To access this media you need to use the download_media tool which takes the message_id and chat_jid (which are shown when printing messages containing the meda), this downloads the media and then returns the file path which can be then opened or passed to another tool.

Technical Details

1. Claude sends requests to the MCP server
2. The MCP server queries the Go bridge for WhatsApp data or directly to the SQLite database
3. The Bridge accesses the WhatsApp API and keeps the SQLite or Postgres database up to date
4. Data flows back through the chain to Claude
5. When sending messages, the request flows from Claude through the MCP server to the bridge and to WhatsApp

Authentication Issues

• QR Code Not Displaying: If the QR code doesn't appear, try restarting the authentication script. If issues persist, check if your terminal supports displaying QR codes.
• WhatsApp Already Logged In: If your session is already active, the Go bridge will automatically reconnect without showing a QR code.
• Device Limit Reached: WhatsApp limits the number of linked devices. If you reach this limit, you'll need to remove an existing device from WhatsApp on your phone (Settings > Linked Devices).
• No Messages Loading: After initial authentication, it can take several minutes for your message history to load, especially if you have many chats.
• WhatsApp Out of Sync: If your WhatsApp messages get out of sync with the bridge, delete both database files (whatsapp-bridge/store/messages.db and whatsapp-bridge/store/whatsapp.db) and restart the bridge to re-authenticate.

This fork takes the core idea and rebuilds it with a different philosophy:
one language, one binary, clean architecture, and flexible deployment.

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Why This Project Exists

The original project is excellent, but it was designed specifically for Claude Desktop, and its architecture had a few constraints that made extending or deploying it more difficult. This fork was created to solve those pain points.

• *Single Language: Everything in Go The original design split responsibilities: This dramatically simplifies development and distribution.

• Clean Architecture: No Mixed Database Logic Moving all database logic into the bridge

• SQLite or PostgreSQL — Your Choice The original project only supported SQLite.

• Two Communication Modes: STDIO + HTTP The original project was built only for Claude Desktop (STDIO MCP). This makes the project usable far beyond Claude Desktop.

• Docker Support This makes deployment trivial on:

• servers
• containers
• orchestrators
• local development

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Features

• Full WhatsApp client using WhatsMeow
• Pure Go MCP server
• Clean API boundary between MCP and bridge
• SQLite or PostgreSQL support
• STDIO + HTTP modes
• Lightweight Docker image
• Easy deployment with Docker Compose
• No Python dependencies
• No mixed database logic
• Production‑ready architecture

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Credits

This project stands on the shoulders of two major contributors:

Original Author: lharries

The initial idea, architecture, and implementation of WhatsApp‑MCP came from
https://github.com/lharries/whatsapp-mcp

Their work demonstrated how MCP could be used to bridge WhatsApp and Claude Desktop.
This fork would not exist without their project.

WhatsMeow

The WhatsApp client functionality is powered by the incredible Go library:
https://github.com/tulir/whatsmeow

Without WhatsMeow, none of this would be possible.

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Why You Might Use This Fork

Choose this version if you want:

• a cleaner architecture
• a single‑language codebase
• a portable binary
• Docker support
• PostgreSQL support
• HTTP support for automation workflows
• a more maintainable and extensible project

The goal is not to replace the original project but to offer an alternative that fits different needs — especially for developers who prefer Go or want to deploy MCP‑based WhatsApp automation in production environments.