{
  "id": "G03",
  "url": "https://cartforagents.com/guides/product-claim-provenance",
  "title": "Product claim provenance: tie every claim to its value, scope and source",
  "description": "Use a proposed JSON claim record with variant binding, units, conditions, provenance and unknown states; it is not an industry protocol.",
  "answer": "Keep one record per product claim: the exact variant it belongs to, the value and unit, the condition and scope it holds under, whether it affirms or excludes something, the document it came from, when you checked it, and every place it has been copied, with a note on whether each copy still matches. Record unknowns as unknown, with a reason, instead of leaving gaps or guessing. The JSON template below is ready to copy into your own files.",
  "take": "Claims break in the copies: in our catalog snapshot, Shopify's generated spec list dropped the word \"hood\" from a snowsuit's temperature rating. Track every copy and you catch that drift before a shopper does.",
  "summary": "A number on your page is only as good as what it is tied to. Here is a proposed way to keep every product claim tied to its variant, its condition and the document behind it, and to track every copy of it.",
  "claims": [
    {
      "text": "Shopify says some Global Catalog response fields are generated or enriched by Shopify and marked Inferred, including the product description, technical specifications, top features and unique selling points, and that they may vary in accuracy.",
      "source_title": "Shopify: Global Catalog MCP, Inferred response fields",
      "source_url": "https://shopify.dev/docs/agents/catalog/global-catalog",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "Living developer documentation; the date is when we checked it. It does not say how the fields are generated or how any assistant uses them."
    },
    {
      "text": "OpenAI's product feed reference says to omit an unknown value in optional fields, not to use placeholder strings such as \"null\", \"unknown\" or \"n/a\" unless a field lists unknown as valid, and that an empty value does not mean zero or false.",
      "source_title": "OpenAI Commerce: Products (file upload feed reference), Value conventions",
      "source_url": "https://developers.openai.com/commerce/specs/file-upload/products",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "Living reference, checked on this date. It describes what a feed should contain, not how ChatGPT ranks or displays products."
    },
    {
      "text": "The same reference says top-level attributes should match the options in variant_dict and that neither representation reconciles conflicting values for you. Its dimensions object accepts length, width, height and a unit, and no other keys.",
      "source_title": "OpenAI Commerce: Products (file upload feed reference), Item information",
      "source_url": "https://developers.openai.com/commerce/specs/file-upload/products",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "We infer from the field list that the feed has no slot for a measurement condition; the reference does not say so in words."
    },
    {
      "text": "In OpenAI's feed reference, a review_count of zero means no reviews while an omitted count means unknown, and an omitted shipping_price means unknown, not free shipping.",
      "source_title": "OpenAI Commerce: Products (file upload feed reference), Reviews and Q&A; Fulfillment",
      "source_url": "https://developers.openai.com/commerce/specs/file-upload/products",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "Feed semantics for OpenAI uploads only. Other platforms may treat blanks differently."
    },
    {
      "text": "OpenAI's merchant page says Shopify and Etsy catalogs are already integrated with no additional setup or application, and says richer data helps products surface with more accurate information when shoppers compare options.",
      "source_title": "OpenAI: Power product discovery in ChatGPT (merchants page)",
      "source_url": "https://chatgpt.com/merchants/",
      "source_date": "2026-10-27",
      "method": "vendor-claim",
      "limitation": "A marketing page, checked on this date. It does not define \"richer data\" or give any measured effect."
    },
    {
      "text": "For \"humidifier for dry winter air large room quiet top fill\", position 5's description said \"up to 32 hours\" of runtime while the Shopify-generated spec list in the same record said \"Up to 36 hours\".",
      "source_title": "Cart for Agents: Receipts cited by our guides (Shopify agent-catalog snapshot, Oct 26, 2026)",
      "source_url": "https://cartforagents.com/research/agent-shopping-research#receipts-cited-by-our-guides",
      "source_date": "2026-10-26",
      "method": "observed",
      "limitation": "One record in one unpersonalized snapshot. We do not know which runtime is right."
    },
    {
      "text": "In the same position-5 record, the description describes a \"4-inch mist outlet\", while the generated spec list gives \"Mist Output: 4 inches (10.16 cm) with 30° tilting\" and dimensions of \"102 cm (L) x 10.16 cm (H) x 11.02 cm (W)\". The description we received gives no dimensions.",
      "source_title": "Cart for Agents: Shopify agent-catalog snapshot, Oct 26, 2026 (How we checked, this page)",
      "source_url": "https://cartforagents.com/guides/product-claim-provenance#how-we-checked",
      "source_date": "2026-10-26",
      "method": "observed",
      "limitation": "We cannot see what Shopify used to generate these lists; the values may come from merchant data we did not receive. We did not check the product or its manual."
    },
    {
      "text": "In the snapshot for \"toddler snowsuit rated for minus 30\", position 9's description rates the hood's insulation to -30°C, and the generated spec line in the same record drops the word hood.",
      "source_title": "Cart for Agents: Receipts cited by our guides (Shopify agent-catalog snapshot, Oct 26, 2026)",
      "source_url": "https://cartforagents.com/research/agent-shopping-research#receipts-cited-by-our-guides",
      "source_date": "2026-10-26",
      "method": "observed",
      "limitation": "One record. The full garment rating is unknown to us."
    },
    {
      "text": "In the snapshot for \"anti theft backpack for city travel\", position 8's description says \"Depth: 2.4lbs\", and the generated spec list says \"Depth 2.4 in\".",
      "source_title": "Cart for Agents: Receipts cited by our guides (Shopify agent-catalog snapshot, Oct 26, 2026)",
      "source_url": "https://cartforagents.com/research/agent-shopping-research#receipts-cited-by-our-guides",
      "source_date": "2026-10-26",
      "method": "observed",
      "limitation": "It looks as if a weight became a depth, but we cannot prove how the generated value was produced, and we do not know the true size."
    },
    {
      "text": "Position 4 of the humidifier search states two exclusions in its description: \"no filter to replace\" and \"Manual mist controls rather than a programmable humidistat\". The record carried no generated metadata.",
      "source_title": "Cart for Agents: Shopify agent-catalog snapshot, Oct 26, 2026 (How we checked, this page)",
      "source_url": "https://cartforagents.com/guides/product-claim-provenance#how-we-checked",
      "source_date": "2026-10-26",
      "method": "observed",
      "limitation": "Quoted from the catalog record, not checked against the product."
    },
    {
      "text": "Across 162 searches in the snapshot, a product-level rating was absent on 440 of 1,620 returned listings; 106 of those carried a rating on the first variant and 334 had neither. No rating had a count of zero.",
      "source_title": "Cart for Agents: Receipts cited by our guides (Shopify agent-catalog snapshot, Oct 26, 2026)",
      "source_url": "https://cartforagents.com/research/agent-shopping-research#receipts-cited-by-our-guides",
      "source_date": "2026-10-26",
      "method": "observed",
      "limitation": "Occurrences, not distinct products. An absent rating is unknown: not zero reviews, and not proof that no rating exists elsewhere."
    },
    {
      "text": "Schema.org's PropertyValue type provides minValue, maxValue, propertyID and measurementTechnique, and unitCode takes a UN/CEFACT code or a URL.",
      "source_title": "Schema.org: PropertyValue; unitCode",
      "source_url": "https://schema.org/PropertyValue",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "Vocabulary definitions only. Schema.org notes that PropertyValue may not trigger the same effect as a specific property, and nothing here says any assistant reads these fields."
    },
    {
      "text": "Shopify says Catalog Mapping can source product data stored in custom fields such as metafields and metaobjects.",
      "source_title": "Shopify Help Center: Shopify Catalog and product discovery for agentic storefronts",
      "source_url": "https://help.shopify.com/en/manual/online-sales-channels/agentic-storefronts/products",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "Living help page. It does not promise every mapped field reaches every assistant unchanged."
    },
    {
      "text": "Global Catalog separates discovery, where results are clustered into one product with offers from several merchants, from evaluation of a specific product or variant, where options, price and the seller checkout link are retrieved.",
      "source_title": "Shopify: Global Catalog MCP, How it works",
      "source_url": "https://shopify.dev/docs/agents/catalog/global-catalog",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "Describes the catalog interface, not the final choice an assistant shows a shopper."
    },
    {
      "text": "Shopify Catalog requires the store to be on the Starter plan or higher, with an exception: stores on Shopify's Agentic plan that have not published their online store to a paid plan can still have products included through agentic storefronts.",
      "source_title": "Shopify Help Center: Requirements for being included in Shopify Catalog",
      "source_url": "https://help.shopify.com/en/manual/shopify-catalog/requirements",
      "source_date": "2026-10-27",
      "method": "documented",
      "limitation": "Living help page, checked on this date. Other requirements (product, account standing, excluded categories) also apply."
    },
    {
      "text": "eCommerce Insights defines agentic commerce optimization with the product record, not the marketing page, as the unit of work, and credits ReFiBuy with the term.",
      "source_title": "eCommerce Insights: What is Agentic Commerce Optimization (ACO)?",
      "source_url": "https://ecommerceinsights.ai/resources/guides/what-is-agentic-commerce-optimization/",
      "source_date": "2026-05-18",
      "method": "vendor-claim",
      "limitation": "A vendor's definition, used here as prior art. It does not propose a claim-level record."
    }
  ],
  "sources": [
    {
      "title": "Shopify: Global Catalog MCP",
      "url": "https://shopify.dev/docs/agents/catalog/global-catalog",
      "accessed": "2026-10-27"
    },
    {
      "title": "OpenAI Commerce: Products (file upload feed reference)",
      "url": "https://developers.openai.com/commerce/specs/file-upload/products",
      "accessed": "2026-10-27"
    },
    {
      "title": "OpenAI: Power product discovery in ChatGPT",
      "url": "https://chatgpt.com/merchants/",
      "accessed": "2026-10-27"
    },
    {
      "title": "Shopify Help Center: Requirements for being included in Shopify Catalog",
      "url": "https://help.shopify.com/en/manual/shopify-catalog/requirements",
      "accessed": "2026-10-27"
    },
    {
      "title": "Shopify Help Center: Shopify Catalog and product discovery for agentic storefronts",
      "url": "https://help.shopify.com/en/manual/online-sales-channels/agentic-storefronts/products",
      "accessed": "2026-10-27"
    },
    {
      "title": "Schema.org: PropertyValue",
      "url": "https://schema.org/PropertyValue",
      "accessed": "2026-10-27"
    },
    {
      "title": "Schema.org: unitCode",
      "url": "https://schema.org/unitCode",
      "accessed": "2026-10-27"
    },
    {
      "title": "eCommerce Insights: What is Agentic Commerce Optimization (ACO)?",
      "url": "https://ecommerceinsights.ai/resources/guides/what-is-agentic-commerce-optimization/",
      "accessed": "2026-10-27"
    },
    {
      "title": "ReFiBuy: What is Agentic Commerce Optimization?",
      "url": "https://refibuy.ai/guides/what-is-agentic-commerce-optimization",
      "accessed": "2026-10-27"
    },
    {
      "title": "Cart for Agents: Receipts cited by our guides",
      "url": "https://cartforagents.com/research/agent-shopping-research#receipts-cited-by-our-guides",
      "accessed": "2026-10-27"
    }
  ],
  "limitations": [
    "The claim record is our proposal. It is not an industry protocol or a platform requirement, no assistant is known to read it, and we have not measured any effect on picks, rank or sales.",
    "The worked examples come from one unpersonalized Shopify agent-catalog snapshot taken on October 26, 2026. We saw the record the catalog returned, not the merchant's source documents, so every evidence field we fill from the outside is unknown.",
    "Shopify marks the description itself as Inferred, so even the description we received may not be the merchant's exact words.",
    "Where a generated value does not appear in the text we received, we cannot tell where it came from. It may come from merchant data we did not see.",
    "A complete record does not make a product fit, safe or more likely to be chosen. It makes wrong copies easier to catch.",
    "Store and brand names are withheld. Quoted excerpts are kept short."
  ],
  "related": [
    "https://cartforagents.com/guides/agent-ready-product-data",
    "https://cartforagents.com/guides/product-specification-template",
    "https://cartforagents.com/guides/product-constraint-coverage",
    "https://cartforagents.com/guides/negative-product-attributes",
    "https://cartforagents.com/guides/agent-commerce-optimization",
    "https://cartforagents.com/research/agent-shopping-research"
  ],
  "published": "2026-10-27",
  "updated": "2026-10-27",
  "checked": "2026-10-27",
  "kind": "guide"
}