Google MCP Server

A Python FastAPI server that exposes Google Docs and Gmail tools with terminal-based approval before each action.

Features

• POST /append_to_doc — Append text to a Google Doc
• POST /create_email_draft — Create a Gmail draft
• Approval gate — Every action prints its name and payload, then waits for y in the terminal before executing

Project Structure

google-mcp-server/
├── server.py          # FastAPI app with tool endpoints
├── auth.py            # Google OAuth authentication
├── docs_tool.py       # Google Docs tool (append content)
├── gmail_tool.py      # Gmail tool (create draft)
├── requirements.txt   # Dependencies
├── credentials.json   # OAuth client secrets (not committed)
└── token.json         # Saved OAuth token (not committed)

Prerequisites

1. A Google Cloud project
2. Google Docs API and Gmail API enabled
3. OAuth 2.0 Desktop app credentials downloaded as credentials.json

Google Cloud setup

1. Go to Google Cloud Console → APIs & Services → Library.
2. Enable Google Docs API and Gmail API.
3. Go to APIs & Services → Credentials → Create Credentials → OAuth client ID.
4. Application type: Desktop app.
5. Download the JSON file and save it as credentials.json in this directory.
6. Under OAuth consent screen, add your Google account as a test user (if the app is in testing mode).

Installation

cd google-mcp-server
python -m venv .venv
source .venv/bin/activate   # Windows: .venv\Scripts\activate
pip install -r requirements.txt

Place credentials.json in the project root before starting the server.

First-time authentication

On the first API call that needs Google access, a browser window opens for OAuth login. After you approve, a token.json file is created. Subsequent runs reuse that token (refreshing it automatically when expired).

Run the server

python server.py

Or with uvicorn directly:

uvicorn server:app --host 127.0.0.1 --port 8000 --reload

The server runs at http://127.0.0.1:8000. Interactive API docs: http://127.0.0.1:8000/docs.

Important: Run the server in a terminal where you can type y or n when prompted. Approval happens in that terminal, not in the HTTP client.

Usage examples

Append to a Google Doc

Find the document ID in the URL:

https://docs.google.com/document/d/DOCUMENT_ID/edit

curl -X POST http://127.0.0.1:8000/append_to_doc \
  -H "Content-Type: application/json" \
  -d '{
    "doc_id": "YOUR_DOCUMENT_ID",
    "content": "\nHello from the MCP server!"
  }'

The server terminal will show:

Action: append_to_doc
Payload: {'doc_id': '...', 'content': '...'}
Approve? (y/n):

Type y to proceed.

Create a Gmail draft

curl -X POST http://127.0.0.1:8000/create_email_draft \
  -H "Content-Type: application/json" \
  -d '{
    "to": "recipient@example.com",
    "subject": "Test draft",
    "body": "This is a draft created via the MCP server."
  }'

Approve in the server terminal when prompted. Check Gmail → Drafts for the new message.

OAuth scopes

Scope	Purpose
https://www.googleapis.com/auth/documents	Read and edit Google Docs
https://www.googleapis.com/auth/gmail.compose	Create and manage Gmail drafts

Troubleshooting

Issue	Fix
credentials.json not found	Download OAuth desktop credentials from Google Cloud Console
Access blocked during login	Add your account as a test user on the OAuth consent screen
403 from API	Type y at the approval prompt in the server terminal
Token errors	Delete token.json and re-authenticate

Security notes

• Never commit credentials.json or token.json.
• This server is intended for local development with manual approval.
• Do not expose it to the public internet without proper authentication.