makeshop: Fixing Double Structured Data Output

When you add JSON-LD to a product page in makeshop's Creator Mode, the Rich Results Test may detect two Product entries and report an error.

This means the structured data makeshop outputs as standard and the JSON-LD you added are both on the same page with the same type. Structured data is a description of a page's content written in a form machines can read. The validation tool can't decide which one is correct, so it reports errors or warnings. When there's an error, the whole block may be ignored, and the result can be worse than before you added anything.

This article covers how to find double output, the criteria for deciding which one to keep, and how to safely add only the types missing from the standard output.

Conclusion: Check the standard output first, and don't add the same type. Add only what's missing

Key idea: More structured data isn't better. A page with two of the same type is harder to handle than a page with none. It's like a clerk wearing two name tags: you don't know which name to use. Before adding, start by subtracting.

How to find double output

1. Run the product page URL through the Rich Results Test

2. Look at the list of detected types. Two or more of the same type means double output

3. Open the page source and search for application/ld+json. If it appears two or more times, identify whether each comes from the standard template or from what you added

4. Run the same check on category pages and the top page

To find where makeshop's standard output sits in the template, search for ld+json inside the Creator Mode template. Start by running a product page through the Rich Results Test once.

Deciding which one to keep

In most cases, keeping the standard and deleting the addition is the right call. When standard values differ from the screen, don't override the JSON-LD; fix the source product data (price, stock, product name). Fixing only the JSON-LD gets reverted at the next update. It's like rewriting a price tag: if the register data is old, the checkout goes back to the original amount. Delete the addition, then check whether the standard values match the screen.

Safely adding the missing types

Add only the types the standard output doesn't include. The ones makeshop tends not to output as standard are BreadcrumbList and Article on content pages.

There are only three principles when adding.

• Fill values dynamically with Creator Mode's own tags. Don't write fixed strings

• Confirm the added type doesn't overlap with a type in the standard output

• After adding, re-verify on three kinds of product page (normal, out of stock, with variations)

When the standard output lacks attributes

Sometimes attributes are missing, such as the standard Product carrying no brand name or product code. In that case, rather than adding a whole Product, choose one of the following.

• Disable the standard output and consolidate on your own JSON-LD. The switch is under Shop Setup > Settings > SEO/SNS/Marketing > Access-analytics tag settings (menu labels are in Japanese in the admin)

• If you don't disable it, keep the standard and give up the missing attributes. Missing attributes do less harm than double output

Keeping what you added intact

Structured data added in Creator Mode can break every time the template changes. The same goes for changes in makeshop's specifications. Being correct on the day it was added is no guarantee it's correct three months later. Like watering a plant, it isn't done once and finished.

Search OS continuously verifies the state of structured data output on existing shops, including makeshop. It detects double output, mismatches with the screen, and breakage after template changes, and compiles them as fix candidates. Bot logs also confirm whether search engines and AI crawlers are actually fetching the pages. It doesn't do the adding for you; it is a layer that keeps watching whether what was added is still correct today. Record the day you change a template, and re-verify afterward.

Frequently asked questions

What happens if I leave double output alone?

Validation errors persist, and rich results may stop showing. AI search finds contradictory structured data hard to trust and may fail to classify the page.

What if I want to change the contents of the standard output?

The basic approach is to fix the product data (product name, price, stock, images). The standard output is generated from it.

Is the Google Merchant Center integration related to structured data?

Merchant Center is a separate route that passes information through a product feed. If the page's structured data and the feed values differ, Merchant Center may show a mismatch warning. Keep both sets of values aligned.

Related reading

• Can makeshop's Built-In Blog Alone Get Picked Up by AI Search: What's Missing and What to Add

• makeshop and WordPress: Put the Blog on a Separate Domain or Under the Shop

• How Far Can You Trust EC-CUBE SEO Plugins: Criteria for Owning Your Structured Data

• makeshop Not in Search: Four Checks

References

• Google Search Central: Product structured data

• Google Search Central: General structured data guidelines

• Google: Rich Results Test

• Google Merchant Center Help: Structured data for Merchant Center