AI authorship isn’t the issue; thin and duplicated content is. Search engines reward helpful, reliable content whoever wrote it, and demote content that adds nothing — which is exactly what you get if you generate five hundred descriptions from the same template with only the product name changed. The specific risk for ecommerce is manufacturer copy: if you paste the supplier’s description like every other retailer selling that item, you have nothing distinguishing your page. That’s the real problem AI can solve, because generating genuinely different copy grounded in your own reviews, your own customer questions and your own honest limitations produces something no competitor has. The practical rule: every description should contain at least two things that could only come from you — customer language from your reviews, a limitation you’ve observed, or guidance based on questions you’ve actually been asked.

Long enough to answer the questions that stop someone buying, and no longer — which in practice means around 150 to 250 words of prose plus a scannable specifications block for most products. Cheaper, simpler items need less; anything technical, expensive or size-dependent needs more, because the buyer has more to resolve before committing. What matters far more than length is order: most people scan rather than read, so what it is, who it’s for and why it’s worth the price must come before the specifications. Two useful tests. First, could someone decide from the first three lines whether to keep reading? Second, does every remaining sentence do a job — answer a question, handle an objection, supply a fact — or is it there for atmosphere? Cut everything in the second category, and length stops being a question you have to think about.

For a bulk run, no — but you don’t have to check all five hundred individually either. The workable approach is to test the prompt thoroughly on five to ten products first and read those in full, because most errors are systematic rather than random: if the prompt is producing an invented claim or a wrong formatting pattern, it’ll do it consistently and you’ll catch it in the sample. Then run the batch and spot-check perhaps one in ten, plus every product in a regulated category and every one where a specification is unusual. What you must check individually: anything with a certification, safety claim, ingredient list, age rating or dimension that matters for fit. The risk isn’t that the model writes clumsy prose across a catalogue — it’s that it invents one plausible detail that becomes a misdescription, and those cluster in exactly the products where being wrong is expensive.

Then getting the facts is your first job and it’s not optional. Ask the supplier for a full specification sheet — materials, dimensions, weight, country of manufacture, certifications, care instructions — and keep it on file, because if a claim on your listing is challenged, “the supplier told me” is a considerably better position than an invented specification. Where the supplier won’t or can’t provide something, measure it yourself and say what you know rather than filling the gap. It’s entirely acceptable for a description to omit a detail; it isn’t acceptable to state one you haven’t verified. For anything regulated — food, cosmetics, electricals, children’s products, anything with a safety standard — you carry obligations as the seller regardless of who manufactured it, so establish what those are before listing rather than after a complaint.