Google Merchant Center Feed Checker Skill

Find the feed problems that get products disapproved or limited in Google Shopping and free listings before you upload: one command, a readable report, and a fixed copy for the formatting mistakes.

python3 -m gmcfeed check products.tsv                                   # TSV, CSV, RSS 2.0 or Atom XML (g: namespace)
python3 -m gmcfeed check products.tsv --fix products.fixed.tsv --currency USD
python3 -m gmcfeed check feed.xml --issues issues.csv --json

• Required attributes: id (unique, max 50), title (max 150), description (max 5,000), link, image_link, availability, price.
• Formats: prices as 19.99 USD (period decimal, ISO 4217), sale price lower than price and in the same currency, ISO 8601 dates and sale date ranges, http(s) URLs, image file types (JPEG, WebP, PNG, GIF, BMP, TIFF), placeholder images, supported values in English (in_stock, new, unisex, yes...), unit pricing units and base measures, multipack, shipping country:region:service:price.
• Identifiers: GTIN length and check digit (UPC, EAN, JAN, ISBN-13, ITF-14), ISBN-10, brand for new products, GTIN or MPN, identifier_exists conflicts.
• Rules that depend on other attributes: preorder needs availability_date, backorder should have one, apparel needs age_group, gender and color (and size for Clothing and Shoes), variants in an item_group_id must differ in color, size, material, pattern, age_group or gender, duplicate variant combinations.
• Quality: all-caps or promotional titles ("free shipping", "% off"), description repeating the title, unknown or misspelled attribute names (Image Link -> additional_image_link), shifted columns from stray tabs, non-UTF-8 files.

Formatting only, each logged in *.changes.csv: supported values (In Stock -> in_stock), prices ($1,299.50 -> 1299.50 USD, 24,00 EUR -> 24.00 EUR), GTIN spaces and dashes, attribute-name casing, UTF-8. It never invents identifiers, changes prices' values or removes products.

skills/merchant-feed/SKILL.md tells Claude Code (or any agent that reads skills) how to run the check, explain disapproval risks and offer fixes. Copy the folder into .claude/skills/; the kit is also a Claude Code plugin (.claude-plugin/plugin.json).

Run ./demo.sh for the example (7 items, 28 issues) and ./run_tests.sh for the tests. Python 3.9+, no dependencies, works offline; your feed never leaves your computer.

Checks the feed file against Google's Product data specification (checked Nov 9, 2026). It can't see your landing pages, image sizes, Merchant Center account settings or policy reviews, so a clean report doesn't guarantee approval. Country-specific rules (shipping and tax requirements, energy labels) are only partly covered.

Pairs with the Shopify and WooCommerce Product CSV Checker Skills. License: LICENSE.txt.