mcp-gtm-ga4

MCP server for Google Tag Manager and GA4 -- tag management, consent auditing, workspace versioning, and analytics reporting via Claude.

Features

• 14 tools spanning GTM workspace management (tags, triggers, variables), consent compliance auditing, workspace preview/versioning, and GA4 reporting
• Sandbox safety -- all write operations verify they target the resolved workspace, refusing to write to non-sandbox workspaces
• Multi-client support -- configure per-client via environment variables
• Auto-detects Default Workspace ID -- no need to manually specify workspace IDs unless using a custom sandbox

Installation

npm install mcp-gtm-ga4

Or clone and build:

git clone https://github.com/mharnett/mcp-gtm-ga4.git
cd mcp-gtm-ga4
npm install
npm run build

Configuration

Security: Never share your .mcp.json file or commit it to git -- it may contain API credentials. Add .mcp.json to your .gitignore.

All configuration is via environment variables. No config.json file is needed.

| Variable | Required | Description | |---|---|---| | GOOGLE_APPLICATION_CREDENTIALS | Yes | Path to a GCP service account JSON key file | | GTM_ACCOUNT_ID | Yes | GTM account ID | | GTM_CONTAINER_ID | Yes | GTM container ID | | GA4_PROPERTY_ID | Yes | GA4 property ID | | GTM_SANDBOX_WORKSPACE_ID | No | Override workspace ID (auto-detects Default Workspace if omitted) | | MCP_SERVER_NAME | No | Server name (defaults to package name mcp-gtm-ga4) |

See config.example.json for a reference template.

Usage

Claude Code (.mcp.json)

{
  "mcpServers": {
    "gtm-ga4": {
      "command": "node",
      "args": ["/path/to/mcp-gtm-ga4/dist/index.js"],
      "env": {
        "GOOGLE_APPLICATION_CREDENTIALS": "/path/to/service-account.json",
        "GTM_ACCOUNT_ID": "1234567890",
        "GTM_CONTAINER_ID": "9876543",
        "GA4_PROPERTY_ID": "331956119"
      }
    }
  }
}

npx

GTM_ACCOUNT_ID=1234567890 \
GTM_CONTAINER_ID=9876543 \
GA4_PROPERTY_ID=331956119 \
GOOGLE_APPLICATION_CREDENTIALS=/path/to/sa.json \
npx mcp-gtm-ga4

Claude Desktop: Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows).

Safety

Workspace sandbox protection

All write operations (gtm_update_tag, gtm_create_tag, gtm_preview, gtm_create_version) verify they target the resolved workspace before executing. If a request attempts to write to a different workspace, the server returns a SafetyError and blocks the operation.

This prevents accidental production changes when the MCP server is configured against a sandbox workspace.

Tools

GTM Tags

| Tool | Description | |---|---| | gtm_list_tags | List all tags in the workspace with consent status and firing triggers | | gtm_get_tag | Get full tag configuration by tag ID | | gtm_update_tag | Update an existing tag (merge patch via JSON) | | gtm_create_tag | Create a new tag from a JSON definition |

GTM Structure

| Tool | Description | |---|---| | gtm_list_triggers | List all triggers (ID, name, type) | | gtm_list_variables | List all variables (ID, name, type) |

GTM Consent

| Tool | Description | |---|---| | gtm_audit_consent | Audit all tags for consent configuration compliance |

GTM Workspace

| Tool | Description | |---|---| | gtm_preview | Generate a quick preview of the current workspace | | gtm_create_version | Create a new container version from the workspace |

GA4 Reports

| Tool | Description | |---|---| | gtm_ga4_run_report | Run a GA4 report with dimensions, metrics, date range, and filters | | gtm_ga4_realtime_report | Run a GA4 realtime report (last 30 minutes) |

GA4 Admin

| Tool | Description | |---|---| | gtm_ga4_list_custom_dimensions | List all custom dimensions for the property | | gtm_ga4_create_custom_dimension | Create a new custom dimension |

Architecture

• GTM API: googleapis (Tag Manager v2)
• GA4 Data: @google-analytics/data (BetaAnalyticsDataClient)
• GA4 Admin: @google-analytics/admin (AnalyticsAdminServiceClient)
• Resilience: cockatiel (retry, circuit breaker, timeout policies)
• Logging: pino with pino-pretty
• Transport: MCP SDK stdio transport

License

MIT

Author

Built by Mark Harnett / drak-marketing