Checkout mode. Example: self

Cart-level comment. Example: 'Please deliver after 6 PM'

Delivery slots (article-level delivery windows). Example: { slots: [{ start: '10:00', end: '12:00' }] }

Gift details per article. Example: [{ article_id: '5fdc737e3c05146138192f79', gift_message: 'Happy Birthday!' }]

GSTIN to add to the cart. Example: '27AAACI1195H1ZK'

Customer contact details for store pickup. Example: { name: 'John', phone: '9876543210' }

Custom cart metadata. Example: { channel: 'web' }

Alternate pickup person details.