Clarity describes inclusions and blemishes. Diamond reports use lettered clarity grades; a coloured-stone listing may instead describe what is visible without magnification.
Eye-clean means no inclusions are visible to the unaided eye. Included means some are visible. These terms describe visibility, rather than replacing the rest of a condition report.
Read the clarity description together with the photographs, condition notes and any supplied report. Check the wording for the individual lot, and ask about an unclear detail before bidding.