Dresses are the hardest single garment to describe well, and the one where description quality most visibly moves a sale. A dress listing that says "blue midi dress" competes on price alone. One that says "cornflower-blue satin slip midi with a cowl neckline, adjustable spaghetti straps and a side slit, bias-cut for a fluid drape" ranks for the searches real buyers type, answers the questions that otherwise become messages ("what's the neckline like?", "is it stretchy?"), and signals a seller who knows what they are selling.
The vocabulary is the bottleneck. Necklines alone span sweetheart, cowl, square, halter, boat, off-the-shoulder; sleeves run bishop, puff, raglan, dolman, flutter; lengths and cuts have their own taxonomy from mini to maxi, sheath to fit-and-flare. Most sellers know the dress they are holding is lovely and do not have those words on tap. Upload the photo, choose the resale purpose, and the description comes back with the neckline, sleeve, length, cut, fabric and closure named — ready to paste into a Poshmark, Depop, Vinted or eBay listing and then edit with the facts only you know (brand, size, condition, measurements).
Two honest limits. The AI describes what is visible: it cannot read a care label from a distance shot, verify fiber content, or know the label size — add those yourself, and photograph the tag if you want it described. And marketplace buyers forgive a plain description sooner than a wrong one, which is why the tool is instructed to hedge ("appears to be silk") rather than assert what the pixels cannot prove.