Google Tasks MCP Server

Google Tasks MCP Server

Connect an MCP-compatible client to Google Tasks through a private server you run yourself. The server exposes compact tools for reading, searching, summarizing, creating, completing, updating, deleting, and moving Google Tasks.

This project is for self-hosted use. You provide your own Google Cloud OAuth credentials, connect your own Google account, and keep tokens in your own SQLite database.

What You Get

• 19 MCP tools for Google Tasks.
• Local stdio mode for desktop/client-launched setups.
• Streamable HTTP mode for local HTTP or VPS hosting.
• Bearer-token HTTP auth, plus optional OAuth 2.0 gateway mode for MCP clients that support OAuth.
• Compact responses designed for low-context assistant workflows.
• Optional operator-managed multi-account bearer-token routing, for familiar setups such as one personal account and one work account.

Choose A Transport

For deeper hosting and distribution guidance, see MCP_SERVER_GUIDE.md and DISTRIBUTION.md.

Container persistence

For a bearer-only single-account HTTP deployment whose filesystem is recreated on startup, GOOGLE_REFRESH_TOKEN can seed an empty SQLite database. It never overwrites an existing token. Keep it in the hosting provider's secret store; do not put it in a start command or Docker build argument. Hosts that provide PORT can use it when BIND_PORT is unset.

OAuth gateway deployments also persist dynamically registered clients and MCP refresh-token hashes. Configure the image's Litestream variables to restore and replicate SQLite to an S3-compatible bucket when the host filesystem is disposable. The container restores the database before starting the server and replicates changes while it runs.

Install

git clone https://github.com/ebmurha/google-tasks-mcp.git
cd google-tasks-mcp
python3.11 -m venv .venv
. .venv/bin/activate
pip install -e .
cp .env.example .env

Generate a bearer token if you will run HTTP mode:

python -c "import secrets; print(secrets.token_urlsafe(48))"

Put the generated value in .env as MCP_BEARER_TOKEN. Do not commit .env.

Google Cloud Setup

1. Create or open a Google Cloud project.
2. Enable the Google Tasks API.
3. Configure the OAuth consent screen.
4. Create an OAuth 2.0 Client ID.

Recommended for local HTTP, VPS, Docker, and other server-style installs:

• Application type: Web application
• Local redirect URI: http://127.0.0.1:8787/callback
• Hosted redirect URI: https://your-domain.example/callback
• .env: set GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET, and GOOGLE_REDIRECT_URI

Local-only alternative:

• Application type: Desktop app
• Download the OAuth client JSON outside this repo.
• Set GOOGLE_OAUTH_KEYS_PATH to that file path.
• Leave GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET empty unless you want env vars to override the JSON file.

Example .env for a local web OAuth client:

GOOGLE_CLIENT_ID=your-client-id.apps.googleusercontent.com
GOOGLE_CLIENT_SECRET=your-client-secret
GOOGLE_REDIRECT_URI=http://127.0.0.1:8787/callback
MCP_BEARER_TOKEN=your-generated-token
DB_PATH=./google-tasks.db
BIND_HOST=127.0.0.1
BIND_PORT=8787

If the Google OAuth app is in Testing mode, add every Google account you bootstrap as a test user, such as both personal and work accounts.

GOOGLE_CLIENT_ID / GOOGLE_CLIENT_SECRET / GOOGLE_OAUTH_KEYS_PATH identify the Google Cloud OAuth app, not the Google Tasks user account. One OAuth client JSON can be reused for several Google users. Each bootstrap run stores a separate refresh token for the Google account you authorize in the browser.

Bootstrap Google OAuth

Hosted HTTP onboarding

For a hosted server, set these independently chosen values:

GOOGLE_REDIRECT_URI=https://your-domain.example/callback
GOOGLE_OAUTH_ONBOARDING_URL=https://your-domain.example/google/oauth
GOOGLE_OAUTH_SETUP_SECRET=generate-a-long-random-operator-password

Configure the public URLs explicitly. The application serves the exact paths from GOOGLE_OAUTH_ONBOARDING_URL and GOOGLE_REDIRECT_URI; it does not retain root-path aliases. The MCP gateway likewise serves the paths declared by MCP_OAUTH_ISSUER and MCP_OAUTH_RESOURCE. A reverse proxy forwards these public paths unchanged. The displayed onboarding link never contains the setup secret.

OAuth-capable MCP clients use one continuous Connect or Reconnect flow. After the server's MCP consent is approved, it verifies the configured Google account. A usable Google credential continues directly to the MCP client. A missing or rejected Google credential continues through Google consent, stores the Google token in SQLite, and then returns to the same MCP client with its original OAuth state and PKCE binding. No token is displayed or copied.

GOOGLE_OAUTH_ONBOARDING_URL remains a separately password-protected recovery page. Open it directly only when explicit operator recovery is needed. If an authenticated MCP tool finds no usable Google token, its error includes this safe recovery URL.

Local and recovery CLI

Run this once per Google account you want the server to access:

google-tasks-mcp-bootstrap

Open the printed URL, approve access, and paste the authorization code back into the terminal.

For multiple trusted accounts on one HTTP server, create one stored bearer token per account and bootstrap each account separately:

google-tasks-mcp-create-bearer-token --account-id personal --label "Personal account"
google-tasks-mcp-bootstrap --account-id personal

google-tasks-mcp-create-bearer-token --account-id work --label "Work account"
google-tasks-mcp-bootstrap --account-id work

Use each printed bearer token only in the matching account's MCP client. The server stores only bearer-token hashes.

Start The Server

HTTP mode:

python -m google_tasks_mcp --transport http

Health check:

curl http://127.0.0.1:8787/healthz

Expected response:

{"ok": true}

Stdio mode:

python -m google_tasks_mcp --transport stdio

Configuration check:

python -m google_tasks_mcp --check

Connect An MCP Client

Remote or local HTTP:

URL:  http://127.0.0.1:8787/mcp
Auth: Bearer <MCP_BEARER_TOKEN>

For a VPS, replace the URL with your HTTPS endpoint:

URL:  https://your-domain.example/mcp
Auth: Bearer <MCP_BEARER_TOKEN>

Local stdio:

{
  "command": "/path/to/google-tasks-mcp/.venv/bin/python",
  "args": ["-m", "google_tasks_mcp", "--transport", "stdio"]
}

MCP_BEARER_TOKEN is not required for stdio because the MCP client launches the process locally.

Authentication Modes

Bearer-token mode is the default HTTP mode. /mcp requires Authorization: Bearer <token>.

• MCP_BEARER_TOKEN routes to account default.
• Tokens created with google-tasks-mcp-create-bearer-token can route different clients to different account_id values.
• Bearer tokens are displayed once and stored only as hashes.

OAuth 2.0 gateway mode is optional. Enable it when your HTTP MCP client supports OAuth authorization metadata and token refresh.

• Set MCP_OAUTH_ISSUER, MCP_OAUTH_CLIENT_ID, MCP_OAUTH_CLIENT_SECRET, and MCP_OAUTH_SIGNING_SECRET.
• Set MCP_OAUTH_RESOURCE to the canonical public MCP URL, or let it default to <issuer>/mcp.
• Set MCP_OAUTH_REDIRECT_URIS to the callback URI values accepted by your MCP client.
• Set MCP_OAUTH_ENABLE_DCR=true for clients that use Dynamic Client Registration.
• The gateway publishes protected-resource and authorization-server metadata, requires PKCE S256, binds tokens to the canonical resource, and includes RFC 9207 issuer identification in authorization redirects.
• /mcp accepts OAuth-issued access tokens and the legacy bearer token.
• OAuth client secrets and refresh tokens are stored only by hash. Registered clients and rotating refresh tokens survive restarts when DB_PATH is durable.

The public proxy URL, MCP OAuth issuer/resource, and Google OAuth callback are operator-controlled deployment settings. They may be changed independently. The server does not require a particular hostname or derive these choices from an owner-specific URL.

MCP OAuth authenticates the client to this server. Google OAuth independently authorizes this server to call Google Tasks. The MCP consent flow coordinates the two layers so Connect and Reconnect cannot finish successfully while the configured Google account is knowingly unusable. The standalone operator page remains available for explicit recovery.

Leave MCP_OAUTH_REDIRECT_URIS empty to keep OAuth gateway mode disabled.

Tools

The same 19 tools are available over stdio, bearer-token HTTP, and OAuth gateway HTTP modes. Tools expose standard MCP titles, descriptions, and safety hints where the client supports them.

All tasklist arguments accept a tasklist ID or exact title. Task title lookup is exact after trimming whitespace and ignores case.

For today, overdue, upcoming, search, and digest, omitting tasklist reads every tasklist. Returned task objects include tasklist_id and tasklist_title; digest labels items with tasklist context.

For list_tasks, clear_completed, single-task tools, and write tools, omitting tasklist uses DEFAULT_TASKLIST, or the first list returned by Google. This prevents unqualified writes from touching every list.

Limitations

These are Google Tasks REST API limits:

• Due dates are date-only. Google drops time-of-day values on task due dates.
• Recurring tasks cannot be created or read through the Google Tasks REST API.
• clear_completed hides completed tasks; it does not permanently delete them.

Docker And VPS

Docker:

docker compose up --build

Keep .env, OAuth JSON files, and SQLite databases outside images and public bundles.

VPS/systemd/Caddy templates are in deploy/:

• deploy/caddy/Caddyfile
• deploy/systemd/google-tasks-mcp.service

Replace every placeholder domain, path, and user before deploying.

Troubleshooting

Missing bearer token:

• HTTP /mcp requires Authorization: Bearer <token> unless OAuth gateway mode is handling the client.
• Stdio mode does not use MCP_BEARER_TOKEN.

Google OAuth app is in Testing mode:

• Add every bootstrapped Google user as a test user.
• Testing-mode refresh tokens can expire after 7 days.

Callback URI mismatch:

• GOOGLE_REDIRECT_URI must exactly match an Authorized redirect URI in Google Cloud.
• For local web OAuth, use http://127.0.0.1:8787/callback consistently.

Expired or revoked Google refresh token:

• For hosted HTTP, open GOOGLE_OAUTH_ONBOARDING_URL and reconnect Google.
• For local or recovery use, run google-tasks-mcp-bootstrap again.
• For multi-account mode, include the same --account-id you used before.

OAuth MCP client keeps re-authorizing:

• Ensure the server is running a version with persisted MCP OAuth refresh tokens.
• Check that DB_PATH points to persistent storage and survives restarts.
• Verify MCP_OAUTH_ISSUER is the public HTTPS base URL with no trailing slash.
• Verify MCP_OAUTH_RESOURCE matches the public /mcp URL exactly.
• On disposable hosts, verify Litestream restored the SQLite replica before startup.

More Docs

• MCP_SERVER_GUIDE.md explains hosting models, credential boundaries, and public project vs public service choices.
• DISTRIBUTION.md explains registry, bundle, and directory publishing.
• .env.example lists every supported environment variable.
• google-tasks-mcp-specifications.md is the behavioral source of truth.

Tests

pytest