Walmart bulk CSVs fail on the same four holes. You do not need an app.

Blank SKU, $0 price, no Main Image URL, two rows sharing a SKU. Drop a Marketplace-style CSV in the browser.

Open the CSV check

How

1. Export or download a Walmart Marketplace item file that includes SKU, Product Name, Price, Main Image URL.
2. Open csv-check.html and drop the file. Nothing is uploaded.
3. Fix the rows that cannot sell. A ranked Monday list of 20 is the Store Audit (USD $149) — email the same CSV to info@shopgaps.com.

ShopGaps is not a Walmart app and does not connect to Seller Center. Full Item Spec files have more columns; the checker still reads SKU, price, and image. WooCommerce merchants who want an on-site plugin can use Catalog Audit.