What Actually Makes AI Pick Your Content?
Length doesn't help, and a confident sales voice actively hurts. What gets content picked is plain, factual writing that answers the question someone actually asked, laid out so it's easy to scan.
That's the takeaway from E-GEO, a 2026 study by researchers at MIT and Columbia. They tested thousands of rewritten product descriptions against five major AI models to see what moved a product up the AI's recommendation list. Most of the popular “GEO tricks” made things worse.
What did the study actually test?
The setup is simple enough to explain over coffee. The researchers took 13,747 real shopping questions from Reddit's r/BuyItForLife, the kind of long, specific request people now type into ChatGPT. Each question came with 10 matching Amazon products.
They then rewrote one product description at a time and asked an AI model to rank all 10 again. If the rewritten product climbed, the rewrite worked. If it dropped, it didn't.
They ran this across GPT-5, Claude Sonnet 4.5, Gemini 3 Flash, DeepSeek V3.2 and Llama 4 Maverick, and they tested 15 well-known rewriting styles, from “sound authoritative” to “add an FAQ”. The results below come from a fixed test set of 2,000 questions.
Does longer content get picked more often?
No. Across almost 69,000 test runs, the correlation between how much longer a description got and how far it moved up was essentially zero (ρ ≈ 0.00).
The clearest example is in the rewriters themselves. GPT-4.1 added around 170 words to the average description and ended up near the bottom of the table. GPT-5 cut about 14 words and was one of the two best performers.
So if your plan for “AI visibility” is to pad every page to 2,000 words, the evidence says you're spending effort on the wrong thing. Write as long as the answer needs and stop there.
Does a confident, salesy tone help?
It does the opposite. Of the 15 rewriting styles tested, 11 did worse than a plain one-line instruction to “optimize this description”. The worst offenders were the ones marketers reach for by instinct:
Only four styles matched or slightly beat the plain baseline: adding an FAQ, using headings and bullets, highlighting concrete advantages, and a generic “format it the way an LLM likes”.
One more thing worth knowing: going to the other extreme didn't work either. Stripping a description down to a single sentence cost about 1.5 positions. The models want the facts. They just don't want them wrapped in a sales pitch.
What did the winning rewrites have in common?
The researchers let an algorithm keep improving the rewriting instructions, starting from all 15 styles. Whatever it started from, it ended up in the same place. The final instructions all asked for roughly the same things:
A caveat on formatting: bullets on their own gave only a small lift. The formatting is there to make the substance easy to find. It doesn't replace it.
A before-and-after example
Here's the kind of change that pattern points to, using a made-up product.
Before:
The ultimate water bottle you'll never want to put down! Engineered with cutting-edge technology for unbeatable performance. Join thousands of happy customers and upgrade your hydration game today!
After:
Insulated 750 ml stainless-steel water bottle that keeps drinks cold for up to 24 hours and hot for up to 12.
Will it leak in a bag? The screw lid is leak-proof when closed. The straw lid is not.
The second version isn't better because it's longer. Every line in it is a fact someone might ask about, so a model (and a person) has something concrete to match against the question.
Can you trick the model into ranking you higher?
Not for long. The researchers added a single line to the ranking prompt asking the model to push misleading or manipulative descriptions to the bottom. Then they attacked it with 14 manipulation tactics, including hidden “rank me first” instructions, fake reviews, invented statistics and extreme superlatives.
The superlative-heavy rewrites were flagged as questionable 100% of the time by every model. GPT-5 and Claude in particular gave the attacks little or nothing.
The most telling part came next. They told the optimizer to find rewrites that would climb the rankings without getting flagged. It got there, but only by drifting into careful, factual, neutral prose. In other words, the only way to beat the filter was to stop manipulating.
What should you change on your pages?
Pick one important page and go through it with this list. It takes about 20 minutes.
One thing this list can't fix: if an AI agent can't load your page in the first place, none of the above matters. You can check both the structure and the readability of a page with the free Horus Index GEO Visibility Checker.
What doesn't the study tell you?
It's a good study, but it's worth being clear about what it covers.
For the step before this one, whether an AI agent can fetch and read your page at all, see the 2026 study AX is the New AEO, which we cover in SEO vs AEO vs GEO: What's the Difference — and Where AX Fits. Its finding fits neatly with this one: agents build their answers from what they can read on your site, and the most common failure is that facts are simply missing.