What is GMC?

GMC is a command-line interface for the Google Merchant API — the successor to the Content API for Shopping. It gives you typed, scriptable, CI-friendly access to your Merchant Center accounts and product data.

It is built around things the Merchant API makes harder than they should be:

• gmc doctor — catches the silent failure mode where a credential authenticates fine but the Cloud project was never registered / the API was never enabled, so calls return cryptic empty results.
• gmc preflight — an offline scanner that flags the attribute, format, policy, and SEO problems that get products disapproved or buried, before you upload.
• gmc migrate — an assistant for moving off the Content API: scope swaps, price-to-micros, identifier remaps, and the feed-label transfer check.
• gmc mcp — an MCP server that exposes 12 tools to AI assistants like Claude Desktop, Cursor, and VS Code Copilot.
• GitHub Action — a first-party CI gate with inline PR annotations, a findings summary, and structured outputs.

Why a CLI

Most Merchant Center work is still done by hand in the web UI. A CLI makes it:

• scriptable — feeds become version-controllable JSON you can diff and review;
• CI-friendly — --json on every command and classed exit codes so pipelines can branch on the failure class;
• honest — doctor tells you why something is broken instead of returning an empty list.

Status

gmc is stable and publicly released at v1.1.0. It covers all 13 stable (v1) Merchant API sub-APIs, including Loyalty Customers, alongside doctor, preflight (including SEO and video-link rules), migrate, feeds-as-code, an MCP server for AI assistants, and a first-party GitHub Action for CI. See the Google compatibility snapshot, release, roadmap, and changelog.

Ready to try it? Head to Getting started.