the.com/whole cloth

means Describing something — usually a lie, excuse, or story — invented completely from scratch, with no basis in fact at all.

from From the literal tailoring sense: a garment cut 'of whole cloth' was made from a single uncut piece of fabric, not stitched together from scraps or remnants. By the 1800s this flipped into the figurative sense we use now — something made entirely from one 'piece,' i.e., invented wholesale, with nothing pieced in from reality. Ironically, the phrase once implied quality and completeness (a whole, unpatched cloth) before it came to mean a complete fabrication.