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 three things the Merchant API makes harder than it 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, and policy problems that get products disapproved, 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.

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 feature-complete (latest v1.0.14). All 11 Merchant API sub-APIs are covered — accounts (incl. developer-registration), products, datasources, inventory, promotions, regions, reports, notifications, quota, issues, conversions, and lfp (Local Feeds Partnership) — alongside the differentiators doctor, preflight, migrate, and feeds-as-code. The API layer tracks Merchant API v1. See the roadmap for the phase breakdown and the changelog for what shipped in each release.

Ready to try it? Head to Getting started.