Google Tagmanager MCP Server

Google Tag Manager MCP

MCP server for the Google Tag Manager API v2: manage containers, workspaces, tags, triggers, variables and publishing from Claude, Cursor, Codex and other AI clients in natural language.

Ask the assistant to audit a container, wire up a new GA4 tag with its trigger, enable built-in variables, compile a version and push it live — the full GTM workflow without clicking through the web UI.

Quick start

1. Get OAuth credentials for a Google Cloud project with the Tag Manager API enabled.

2. Add the server — for example in Claude Code (other clients):

   claude mcp add google-tagmanager \
     -e GOOGLE_TAGMANAGER_CLIENT_ID=your_client_id \
     -e GOOGLE_TAGMANAGER_CLIENT_SECRET=your_client_secret \
     -e GOOGLE_TAGMANAGER_REFRESH_TOKEN=your_refresh_token \
     -- npx -y mcp-google-tagmanager
   

3. Ask the assistant: "List my GTM containers and show which tags fire on page view."

Tools

Built-in rate limiting

The Tag Manager API quota is unusually strict: 0.25 QPS per project (25 requests per 100-second sliding window) and 10,000 requests per day. The server handles this for you:

• every API request goes through a serialized queue with a minimum spacing of 4.2 s between requests (tunable via GOOGLE_TAGMANAGER_MIN_INTERVAL_MS);
• 429 and quota-403 (rateLimitExceeded / userRateLimitExceeded / quotaExceeded) responses are retried with exponential backoff honoring Retry-After;
• 5xx and network errors are retried for reads only — a write that may have committed is never replayed.

Big fan-out requests ("list everything in every container") will therefore be slow by design — that is the quota, not the server.

Example prompts

• "Which tags in container GTM-ABC123 fire on the page-view trigger?"
• "Create a Custom HTML tag in the default workspace that logs to the console, firing on all pages."
• "Enable the clickText and clickClasses built-in variables in my workspace."
• "Compile my workspace into a version named 'March release' and publish it."

Installation

claude mcp add google-tagmanager \
  -e GOOGLE_TAGMANAGER_CLIENT_ID=your_client_id \
  -e GOOGLE_TAGMANAGER_CLIENT_SECRET=your_client_secret \
  -e GOOGLE_TAGMANAGER_REFRESH_TOKEN=your_refresh_token \
  -- npx -y mcp-google-tagmanager

claude_desktop_config.json — macOS ~/Library/Application Support/Claude/, Windows %APPDATA%\Claude\

{
  "mcpServers": {
    "google-tagmanager": {
      "command": "npx",
      "args": ["-y", "mcp-google-tagmanager"],
      "env": {
        "GOOGLE_TAGMANAGER_CLIENT_ID": "your_client_id",
        "GOOGLE_TAGMANAGER_CLIENT_SECRET": "your_client_secret",
        "GOOGLE_TAGMANAGER_REFRESH_TOKEN": "your_refresh_token"
      }
    }
  }
}

~/.cursor/mcp.json (or .cursor/mcp.json in the project)

{
  "mcpServers": {
    "google-tagmanager": {
      "command": "npx",
      "args": ["-y", "mcp-google-tagmanager"],
      "env": {
        "GOOGLE_TAGMANAGER_CLIENT_ID": "your_client_id",
        "GOOGLE_TAGMANAGER_CLIENT_SECRET": "your_client_secret",
        "GOOGLE_TAGMANAGER_REFRESH_TOKEN": "your_refresh_token"
      }
    }
  }
}

For a quick one-off session you can skip the trio and pass a short-lived token directly: GOOGLE_TAGMANAGER_ACCESS_TOKEN=ya29.... (Google access tokens expire after about an hour and are not refreshed automatically).

Getting credentials

The Tag Manager API only supports OAuth 2.0 — there are no API keys for user data. One-time setup:

1. Create/pick a Google Cloud project at console.cloud.google.com and enable the Tag Manager API (direct link). Without a registered project the API grants zero quota — this step is mandatory.
2. Configure the OAuth consent screen (APIs & Services → OAuth consent screen). For personal use, External + your account as a test user is enough.
3. Create an OAuth client (APIs & Services → Credentials → Create credentials → OAuth client ID → Desktop app or Web application). Save the client id and client secret.
4. Mint a refresh token. The easiest path is the OAuth 2.0 Playground:

   • gear icon → check Use your own OAuth credentials → paste the client id/secret (for a Web client also add https://developers.google.com/oauthplayground to its authorized redirect URIs);

   • in Step 1 authorize these scopes (space-separated):

     https://www.googleapis.com/auth/tagmanager.readonly https://www.googleapis.com/auth/tagmanager.edit.containers https://www.googleapis.com/auth/tagmanager.edit.containerversions https://www.googleapis.com/auth/tagmanager.publish
     

   • in Step 2 click Exchange authorization code for tokens and copy the refresh token.

5. Put the three values into the environment variables above. The server exchanges the refresh token for access tokens automatically and caches them until just before expiry.

⚠️ The credentials are stored as plain text in your client's MCP config. Scope the OAuth consent to the four Tag Manager scopes above and nothing else.

Note the scope split: reading needs readonly, editing needs edit.containers, create_version needs edit.containerversions, and publishing needs publish. Authorize all four at once or re-consent mid-flow.

Configuration

* the trio is required unless GOOGLE_TAGMANAGER_ACCESS_TOKEN is set.

Good to know

• create_version deletes the source workspace. The response's newWorkspacePath points to the automatically created replacement — the server surfaces it and the tool description warns the model, but keep it in mind when scripting.
• compilerError: true can arrive with HTTP 200 on create_version and publish. The server converts it into a tool error so it is never mistaken for success.
• Updates are full replacements (PUT, not PATCH): update_entity expects the complete resource. Fetch with get_resource, edit, send back, and pass the fingerprint for optimistic-concurrency safety.
• All ids are strings, and every resource carries its own path field — echo it back rather than assembling paths by hand.

Requirements

• Node.js >= 20
• A Google account with access to at least one GTM container

Documentation

• docs/TOOLS.md — tool reference
• docs/DEVELOPMENT.md — architecture and dev commands
• docs/PUBLISHING.md — release checklist
• Google Tag Manager API v2 reference

Support

Questions and issues → GitHub Issues or Telegram @gistrec.

License

MIT