feat(google-ads): add Google Ads plugin (official google-ads-mcp server)

[SamSokolin]

Adds third_party/google-ads, a plugin for Google's official Google Ads MCP server, and registers it in marketplace.json and the root README. Scaffold mirrors the existing third_party/ plugins (plugin.json, mcp.json, README.md, CHANGELOG.md, LICENSE, assets/logo.svg).

Install config

Google does not publish a hosted remote MCP endpoint for Google Ads (unlike gmailmcp.googleapis.com for Gmail). The official server is a Python package that runs locally over stdio, or that you self-host on Cloud Run. mcp.json therefore uses the exact pipx run configuration from Google's developer integration guide and the repo README:

{
  "mcpServers": {
    "google-ads": {
      "type": "stdio",
      "command": "pipx",
      "args": ["run", "--spec", "git+https://github.com/googleads/google-ads-mcp.git", "google-ads-mcp"],
      "env": {
        "GOOGLE_APPLICATION_CREDENTIALS": "${GOOGLE_APPLICATION_CREDENTIALS}",
        "GOOGLE_PROJECT_ID": "${GOOGLE_PROJECT_ID}",
        "GOOGLE_ADS_DEVELOPER_TOKEN": "${GOOGLE_ADS_DEVELOPER_TOKEN}"
      }
    }
  }
}

This follows the same stdio + variables pattern as third_party/xero. The three env vars are declared as required variables in plugin.json. GOOGLE_ADS_LOGIN_CUSTOMER_ID (manager accounts only) is documented as a manual env addition rather than an optional variable, since no plugin in the repo currently relies on optional-variable substitution. Verified against the server source that GOOGLE_ADS_DEVELOPER_TOKEN is required and credentials are resolved via Application Default Credentials with the https://www.googleapis.com/auth/adwords scope.

No client IDs, secrets, or tokens are bundled.

README

Covers the requested caveats:

• Requires a Google Ads API developer token (with at least Explorer access for production accounts).
• Requires the Ads-specific OAuth scope https://www.googleapis.com/auth/adwords, authorized with the user's own OAuth client in a Cloud project where the Google Ads API is enabled.
• Explicitly states this is not a drop-in reuse of the Gmail/Drive/Calendar Workspace sign-in, and explains why.
• Step-by-step setup (pipx, developer token, enable API, OAuth client, gcloud auth application-default login, configure variables), manager-account note, tool/resource table (the official server is read-only), and the self-hosted Cloud Run http alternative.

Logo

Official Google Ads product icon (geometry and brand colors of https://www.gstatic.com/images/branding/productlogos/ads/v5/192px.svg) on a padded white 192×192 tile, matching the Gmail/Drive/Calendar plugins. Note for reviewers: gstatic.com was not reachable from the agent VM, so the path data was taken from a vendored copy of that icon rather than the gstatic file itself; worth a quick eyeball against the original.

Validation

node scripts/validate-plugins.mjs passes.