Acp product feed fields

OpenAI's product feed spec for ChatGPT (Agentic Commerce Protocol) requires item_id, title (max 150 characters), description (max 5,000, plain text), url, brand, seller_name, image_url, availability (in_stock, out_of_stock, pre_order, backorder or unknown) and price written as amount plus ISO 4217 code ("79.99 USD"); variants also need group_id, listing_has_variations and variant_dict. gtin, mpn, condition, sale_price, accepts_returns and return_policy are recommended. is_eligible_search defaults to true; is_eligible_checkout defaults to false and additionally needs seller_privacy_policy and seller_tos URLs and a separately enabled checkout integration. Feeds are full snapshots pushed by SFTP (parquet preferred; jsonl.gz, csv.gz and tsv.gz accepted) or sent by API, recommended at least daily; a product dropped from snapshots is retained for up to 14 days.