properties /personalization

A buyer-supplied customization the offer collects — the anchor of a qualified bundle, exactly as a media item or a warranty anchors its qualifiers. Its literal value is the field's buyer-facing LABEL as the listing prints it ('Name to engrave', 'Monogram', 'Gift message', 'Jersey number', 'Upload your photo'), so the field is named by what it asks for. Cardinality many, because one product commonly collects several custom fields at once — a jersey taking a name AND a number, a mug taking a photo AND a message — each its own statement riding its own input-type, required-ness and length limit. THE COLLAPSE: engraving, monogram, custom text, printed name, gift message, a made-to-order custom input, a Shopify line-item property, a customizable option are NOT separate forms — each is ONE personalization_field whose label names its purpose and whose input_type says its data-kind (an engraving is a free-text field labelled 'engraving'; a monogram is a free-text field labelled 'monogram' capped at 3 characters). This is grammar only: the buyer's actual entered value — the real name engraved, the photo uploaded, the option chosen — is realised line-item data held downstream (L1), never a pool value (A17: define the slot, not the fill). Distinct from a variation axis (colour/size — a seller-defined split the catalogue prices and stocks as separate cells): a personalization field creates no SKU and its value is captured per order, not priced per cell.