I needed to generate 500 product descriptions for a home goods client by end of week. Their catalog: a spreadsheet with product names, dimensions, materials, and bullet-point features. My deliverable: unique, SEO-optimized copy for each one, ready to paste into Shopify. The manual approach would take 40+ hours. I had two days. Here's the Python pipeline I built, what broke along the way, and the exact code that processed all 500 without blowing the API budget or producing garbage output. What you'll actually build By the end of this tutorial, you'll have a script that: Reads a CSV of product data (name, specs, features) Generates one SEO-optimized description per product via GPT-4o Handles OpenAI rate limits with automatic exponential backoff Validates output quality before writing to disk Saves progress as it runs — so a crash at item 387 doesn't mean starting over Outputs a clean CSV ready for Shopify, WooCommerce, or any CMS Here's what the output looks like for a product called "Mango Wood Serving…