{
  "id": "N05",
  "url": "https://cartforagents.com/guides/clipped-product-descriptions",
  "title": "Product description length for AI shopping: what survives when the description gets cut",
  "description": "AI shopping assistants often read only the start of a product description. We checked where 1,594 real descriptions put their first number, and what a 250-character cut leaves on one humidifier shelf.",
  "answer": "Write as if only the first 250 characters of your description get read, because often that's all an AI assistant uses. Nobody publishes a fixed cutoff, but OpenAI says ChatGPT may write its own simplified descriptions, and one tracking vendor reports ChatGPT cutting descriptions at about 40 words when it scores products. Put the product type and the two or three numbers people buy on at the very top, and keep the long copy underneath.",
  "take": "Long descriptions aren't the problem; buried facts are. In our snapshot of real Shopify listings, most descriptions that state a measurement don't give the first one until after character 250.",
  "summary": "AI assistants rarely read your whole product description. Some shorten it, some cut it off. We measured where real Shopify descriptions put their deciding numbers, then watched our own test hide a room size that was sitting 31 characters past the cut.",
  "claims": [
    {
      "text": "In our supplied-snippet simulation, competitor descriptions were cut to about 215 characters. Two real humidifier listings in the panel stated \"536 ft²\" coverage in their full descriptions, starting at character 246 and character 267, so the number fell outside what the models saw.",
      "source_title": "Cart for Agents: Product description length for AI shopping, How we checked",
      "source_url": "https://cartforagents.com/guides/clipped-product-descriptions#how-we-checked",
      "source_date": "2026-11-04",
      "method": "observed",
      "limitation": "Character positions are counted in the description text after removing HTML tags, from one saved Shopify Catalog response of October 26, 2026."
    },
    {
      "text": "In detailed-brief sessions where GPT-6.1-Sol picked two listings that showed no room size, its stated reason said the room size was not confirmed in all 21 sessions. Every one of those pairs included at least one of the two humidifiers whose full description stated 536 ft².",
      "source_title": "Cart for Agents: Vague vs specific product facts simulation",
      "source_url": "https://cartforagents.com/research/vague-specific-product-facts-simulation",
      "source_date": "2026-11-04",
      "method": "controlled-simulation",
      "limitation": "We re-read the saved reasons from the October 27, 2026 simulation. A model's stated reason is not proof of why it picked."
    },
    {
      "text": "OpenAI says ChatGPT may generate simplified product titles and descriptions based on information it receives from third-party providers.",
      "source_title": "OpenAI Help Center: Shopping with ChatGPT Search",
      "source_url": "https://help.openai.com/en/articles/11128490-shopping-with-chatgpt-search",
      "source_date": "2026-11-04",
      "method": "documented",
      "limitation": "Living help page. It does not say how short the simplified version is or which facts it keeps."
    },
    {
      "text": "Peec AI reports that, in ChatGPT debug data it examined, every product description in a prompt block was cut at exactly 50 tokens, which it equates to roughly 40 words or 250 characters in English, at ChatGPT's scoring stage.",
      "source_title": "Peec AI: ChatGPT Shopping optimization in 2026: US vs. Europe",
      "source_url": "https://peec.ai/blog/chatgpt-shopping-optimization-in-2026-us-vs.-europe",
      "source_date": "2026-11-04",
      "method": "vendor-claim",
      "limitation": "A vendor's reading of undocumented debug data from US sessions. OpenAI has not published a description limit."
    },
    {
      "text": "Shopify marks the Global Catalog description, technical specifications, top features and unique selling points as Inferred: generated or enriched by Shopify, possibly absent or of varying accuracy, and to be treated as discovery signals rather than merchant-authored text.",
      "source_title": "Shopify: Global Catalog MCP, Inferred response fields",
      "source_url": "https://shopify.dev/docs/agents/catalog/global-catalog",
      "source_date": "2026-11-04",
      "method": "documented",
      "limitation": "Living developer documentation. It does not say how often Shopify changes a merchant's description."
    },
    {
      "text": "In our October 26, 2026 snapshot of 162 Shopify Catalog searches (1,612 distinct products), 1,458 of the 1,594 non-empty product descriptions were longer than 250 characters. Of the 760 descriptions that stated at least one measurement with a unit such as dB, L, hours, inches, lbs or ft², 542 gave the first one after character 250.",
      "source_title": "Cart for Agents: Product description length for AI shopping, How we checked",
      "source_url": "https://cartforagents.com/guides/clipped-product-descriptions#how-we-checked",
      "source_date": "2026-11-04",
      "method": "observed",
      "limitation": "Our own pattern match on description text with HTML removed. It counts characters, not tokens, and misses facts written without a number and unit."
    },
    {
      "text": "For \"humidifier for dry winter air large room quiet top fill\", 4 of the top 10 descriptions stated a decibel figure and 4 stated a room size. Within the first 250 characters, 2 stated a decibel figure (positions 2 and 5) and 2 stated a room size (positions 2 and 3). Position 4's description reached \"rated for single rooms up to\" before character 250 and \"400 square feet\" just after it.",
      "source_title": "Cart for Agents: Product description length for AI shopping, How we checked",
      "source_url": "https://cartforagents.com/guides/clipped-product-descriptions#how-we-checked",
      "source_date": "2026-10-26",
      "method": "observed",
      "limitation": "One unpersonalized search, one snapshot. Counts the description field only; Shopify's generated spec lists carried some of these numbers too."
    },
    {
      "text": "For a small Canadian lip gloss brand's gift box, Shopify Catalog received a blank product-level description while the variant record carried the full text.",
      "source_title": "Cart for Agents: Field-tested AI visibility case study",
      "source_url": "https://cartforagents.com/research/ai-product-visibility-case-study",
      "source_date": "2026-10-28",
      "method": "observed",
      "limitation": "One product checked as a Canadian shopper. By November 4, 2026 the product-level description arrived in full."
    }
  ],
  "sources": [
    {
      "title": "OpenAI Help Center: Shopping with ChatGPT Search",
      "url": "https://help.openai.com/en/articles/11128490-shopping-with-chatgpt-search",
      "accessed": "2026-11-04"
    },
    {
      "title": "Peec AI: ChatGPT Shopping optimization in 2026: US vs. Europe",
      "url": "https://peec.ai/blog/chatgpt-shopping-optimization-in-2026-us-vs.-europe",
      "accessed": "2026-11-04"
    },
    {
      "title": "Shopify: Global Catalog MCP",
      "url": "https://shopify.dev/docs/agents/catalog/global-catalog",
      "accessed": "2026-11-04"
    },
    {
      "title": "Cart for Agents: Vague vs specific product facts simulation",
      "url": "https://cartforagents.com/research/vague-specific-product-facts-simulation",
      "accessed": "2026-11-04"
    }
  ],
  "limitations": [
    "Nobody publishes how much of a description each assistant reads. We used 250 characters because that is roughly where one vendor saw ChatGPT cut descriptions, not because it is a known rule.",
    "Our catalog counts come from one unpersonalized Shopify Catalog snapshot taken on October 26, 2026. ChatGPT, Google and others may receive a different version of your description.",
    "We counted numbers with units using a simple pattern match. Facts written in words, like \"fragrance-free\", are not in those counts.",
    "The 215-character cut was a choice we made when we built the simulation. It shows what happens when a fact sits past a cut; it doesn't show where any live assistant cuts.",
    "We haven't tested whether moving a fact to the top of a real listing changes what any assistant recommends, or your sales."
  ],
  "related": [
    "https://cartforagents.com/guides/ai-product-descriptions",
    "https://cartforagents.com/guides/machine-readable-product-data",
    "https://cartforagents.com/guides/agent-commerce-optimization",
    "https://cartforagents.com/guides/product-constraint-coverage",
    "https://cartforagents.com/guides/shopify-global-catalog",
    "https://cartforagents.com/research/vague-specific-product-facts-simulation",
    "https://cartforagents.com/research/quiet-humidifiers",
    "https://cartforagents.com/guides/recommendation-receipts"
  ],
  "published": "2026-11-04",
  "updated": "2026-11-04",
  "checked": "2026-11-04",
  "kind": "guide"
}