Using AI-Generated Schema on Shopify Product Pages

What a Shopify product page already outputs

Before adding anything, find out what is there. Open a product page, view the source and search for application/ld+json. On a typical store you will find markup from up to three places:

• The theme. Recent versions of Dawn and many Online Store 2.0 themes output Product markup with Liquid's structured_data filter, usually in the main product section. Older and third-party themes often have a hand-written block in a snippet.
• A review app. Most review apps add ratings, either inside their own Product block or as a separate one.
• An SEO app. Several apps add or replace Product, Organization and breadcrumb markup, and some have their own settings for it.

Run the product URL through the Rich Results Test and open the Product snippets and Merchant listings items. If one Product appears with no errors and the fields you care about, you may not need generated markup on this template at all. If there are two or three Product items, sort that out first with the duplicates guide, because adding a generated block would make a fourth.

Why a pasted block goes stale on Shopify

The generator reads the product page as it is when you run it. Everything it writes is fixed from then on unless you change it. On a Shopify store, many of those values move without anyone touching the markup:

By contrast, some things the generator does well are stable: the material, the dimensions, care instructions, the intended audience, a clean description, and the choice between Product and ProductGroup. Those are the parts worth keeping as written.

Deciding who owns each property

The simplest reliable arrangement is one Product block per page, built by your theme, with generated content used to improve it. Split the properties like this:

Everything in the Shopify rows is read at page load, so it can never go stale. Everything in the generated rows is stable information that a person checks once per product.

Turning generated output into Liquid

Take one good generated block and replace each moving value with the Liquid that produces it. The json filter wraps text in quotes and escapes anything that would break the block, such as inch marks in a product title. The image_url filter returns an address starting with //, so https: is added in front.

{%- assign v = product.selected_or_first_available_variant -%}
<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "Product",
  "@id": "{{ canonical_url }}#product",
  "name": {{ product.title | json }},
  "url": "{{ canonical_url }}",
  "description": {{ product.metafields.custom.schema_description.value | default: product.description | strip_html | strip_newlines | json }},
  "image": [
    {%- for img in product.images limit: 3 -%}
      "https:{{ img | image_url: width: 1200 }}"{% unless forloop.last %},{% endunless %}
    {%- endfor -%}
  ],
  "sku": {{ v.sku | json }},
  {%- if v.barcode != blank %}
  "gtin": {{ v.barcode | json }},
  {%- endif %}
  {%- if product.metafields.custom.material != blank %}
  "material": {{ product.metafields.custom.material.value | json }},
  {%- endif %}
  "brand": { "@type": "Brand", "name": {{ product.vendor | json }} },
  "offers": {
    "@type": "Offer",
    "url": "{{ canonical_url }}",
    "price": "{{ v.price | divided_by: 100.0 }}",
    "priceCurrency": "{{ cart.currency.iso_code }}",
    "availability": "https://schema.org/{% if v.available %}InStock{% else %}OutOfStock{% endif %}",
    "itemCondition": "https://schema.org/NewCondition"
  }
}
</script>

A few details that matter:

• Prices are stored in pence. v.price is 3400 for £34.00, so it is divided by 100.0. Avoid the money filters here: depending on your store's currency format they can add a sign, a thousands comma or a decimal comma, all of which make the price invalid.
• Currency follows the visitor. With Shopify Markets, a visitor may see prices converted into another currency. cart.currency.iso_code gives the code for the currency the page is showing, so price and currency stay in step.
• Optional fields are wrapped in conditions so that a product with no barcode or material does not produce an empty value.
• Brand from vendor only works if your vendor field holds the brand. Stores that use vendor for a supplier or wholesaler should use a brand metafield instead.

Per-product extras, and moving them in bulk

The parts of generated markup worth keeping, such as a tidy description, material, dimensions or care details, belong in product metafields. Create the definitions once in Settings, Custom data, Products, for example custom.material as single-line text and custom.schema_description as multi-line text. They then appear as fields on every product in the admin, and the Liquid above reads them.

Working through a catalogue

1. Generate markup for a sample of products from each product type and review it against the product pages.
2. Copy the stable values you want to keep into a spreadsheet, one row per product handle, one column per metafield.
3. Check each row against the product. Delete anything that is not stated on the page or in your supplier data.
4. Load the columns into the metafields. Shopify's bulk editor can show metafield columns for editing, and the product CSV import in current versions can include metafield columns; for large catalogues a bulk import app is another option.
5. Spot-check a few products in the Rich Results Test after the import.

Review apps and ratings

Generated markup is at its most dangerous around ratings. The model may read a star widget, a "4.8 from 212 reviews" line or a single testimonial and write an aggregateRating. On Shopify, review widgets usually load with JavaScript after the page, so the generator may have seen stale numbers, placeholder text or nothing at all.

• Delete any rating in the generated block. Ratings must come from a live source that matches what shoppers see.
• Let the review app own ratings. Most review apps output rating markup, and several can also write Shopify's standard product review metafields, reviews.rating and reviews.rating_count. Use one route, not both.
• Check the result after installing or changing a review app. Some apps add a whole second Product block rather than a rating inside yours. If that happens, look in the app's settings for an option to switch its markup off or change its output.

The fix, step by step

Variants, markets and theme updates

Products with variants

The snippet above describes the selected variant, which is what the page shows when opened with a ?variant= parameter and the first available variant otherwise. That is a sound starting point. If you want every variant described, the pattern is a ProductGroup with one Product per variant in hasVariant, which means looping over product.variants in the snippet. Generated markup for a variant product is useful here as a model of the structure, but it will have listed only the variants the model saw, with the prices it saw.

Several markets and domains

If each market has its own domain or subfolder, canonical_url follows the page being viewed, so the markup's addresses stay correct. Keep the currency code dynamic; a generated block with a fixed GBP will be wrong on every non-UK page.

Theme updates

Updating a theme from the theme store creates a new version, and edits you made directly in the theme code may not come across. After any theme update, check that your snippet is still rendered and that the theme's own Product output has not been switched back on. Metafield values are stored against products, not the theme, so they survive.