Introduction

This project provides a Google Chat integration for MCP (Model Control Protocol) servers written by Python with FastMCP. It allows you to access and interact with Google Chat spaces and messages through MCP tools.

Structure

The project consists of two main components:

1. MCP Server with Google Chat Tools: Provides tools for interacting with Google Chat through the Model Control Protocol.

   • Written by FastMCP

   • server.py: Main MCP server implementation with Google Chat tools

   • google_chat.py: Google Chat API integration and authentication handling

2. Authentication Server: Standalone component for Google account authentication

   • Written by FastAPI

   • Handles OAuth2 flow with Google

   • Stores and manages access tokens

   • Can be run independently or as part of the MCP server

   • server_auth.py: Authentication server implementation

The authentication flow allows you to obtain and refresh Google API tokens, which are then used by the MCP tools to access Google Chat data. (Your spaces and messages)

Related MCP server: google-chat-mcp

Features

• OAuth2 authentication with Google Chat API

• List available Google Chat spaces

• Retrieve messages from specific spaces with date filtering

• Read card messages (bots, webhooks, CI notifications) rendered as markdown

• Local authentication server for easy setup

Requirements

• Python 3.13+

• Google Cloud project with the following APIs enabled:

  • Google Chat API

  • People API (for user display names)

• OAuth2 credentials from Google Cloud Console

How to use?

Prepare Google Oauth Login

1. Clone this project

   git clone https://github.com/chy168/google-chat-mcp-server.git
   cd google-chat-mcp-server

2. Prepare a Google Cloud Project (GCP)

3. Google Cloud Conolse (https://console.cloud.google.com/auth/overview?project=<YOUR_PROJECT_NAME>)

4. Google Auth Platform > Clients > (+) Create client > Web application reference: https://developers.google.com/identity/protocols/oauth2/?hl=en Authorized JavaScript origins add: http://localhost:8000 Authorized redirect URIs: http://localhost:8000/auth/callback

5. After you create a OAuth 2.0 Client, download the client secrets as .json file. Save as credentials.json at top level of project.

Authentication

There are two authentication modes available:

Option 1: CLI Mode (Recommended for headless/remote environments)

uv run python server.py --auth cli

This will:

1. Display an authorization URL

2. Open the URL in any browser (can be on another device)

3. Complete Google authorization

4. Copy the redirect URL from browser and paste it back to terminal

5. Token will be saved as token.json

Option 2: Web Mode (For environments with local browser)

uv run python server.py --auth web --port 8000

• Open browser at http://localhost:8000/auth

• Complete Google login

• Token will be saved as token.json

MCP Configuration (mcp.json)

{
    "mcpServers": {
        "google_chat": {
            "command": "uv",
            "args": [
                "--directory",
                "<YOUR_REPO_PATH>/google-chat-mcp-server",
                "run",
                "server.py",
                "--token-path",
                "<YOUR_REPO_PATH>/google-chat-mcp-server/token.json"
            ]
        }
    }

Docker / Podman

Run Container

# Mount your project directory containing token.json
docker run -it --rm \
  -v /path/to/your/project:/data \
  ghcr.io/chy168/google-chat-mcp-server:latest \
  --token-path=/data/token.json

# or with podman
podman run -it --rm \
  -v /path/to/your/project:/data \
  ghcr.io/chy168/google-chat-mcp-server:latest \
  --token-path=/data/token.json

Run Auth Server in Container

# Web mode
docker run -it --rm \
  -p 8000:8000 \
  -v /path/to/your/project:/data \
  ghcr.io/chy168/google-chat-mcp-server:latest \
  --auth web --host 0.0.0.0 --port 8000 --token-path=/data/token.json

# CLI mode (for headless environments)
docker run -it --rm \
  -v /path/to/your/project:/data \
  ghcr.io/chy168/google-chat-mcp-server:latest \
  --auth cli --token-path=/data/token.json

Tools

The MCP server provides the following tools:

Google Chat Tools

• get_chat_spaces() - List all Google Chat spaces the bot has access to

• get_space_messages(space_name: str, start_date: str, end_date: str = None) - List messages from a specific Google Chat space with optional time filtering

• search_messages(space_name: str, query: str, start_date: str = None, end_date: str = None) - Case-insensitive substring search in message text and card text

Card messages

Bots and webhooks (CI, monitoring, alerting) usually post cards and leave the message text empty. Such messages get an extra cards_text field holding the cards rendered as markdown: card and section headers as headings, labelled values as list items, and buttons and clickable texts as links.

{"sender": "CI", "text": null, "cards_text": "## ❌ my-pipeline #42\n\n_Build failed_\n\n- **Duration** : 11 sec\n[Open build](https://ci.example.com/42)"}

Development and Debug

Build Image

docker build -t google-chat-mcp-server:latest .
# or
podman build -t google-chat-mcp-server:latest .

Debug

fastmcp dev server.py --with-editable .

Run Tests

uv run python -m unittest discover -s tests -t .

The same suite runs in GitHub Actions on every push and pull request (.github/workflows/test.yml).