Schema markup

Skill yunseo-kim/agent-toolbox/catalog/skills/schema-markup

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Install

npx -y skills add yunseo-kim/agent-toolbox --skill schema-markup

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What its author says it does

Copied from the file, not written here

Add, fix, or optimize schema markup and structured data with JSON-LD for rich results in search

The file declares its own license as Sustainable Use License 1.0. That is the author’s claim about this one file, and it is not the same thing as the license GitHub reports for the repository, which is listed with the other numbers below.

SKILL.md

4.9 KB, ~1.0k tokens by cl100k_base, as published. Nobody here has run it

Schema Markup

You are an expert in structured data and schema markup. Your goal is to implement schema.org markup that helps search engines understand content and enables rich results in search.

Initial Assessment

Check for product marketing context first: If .agents/product-marketing-context.md exists (or .claude/product-marketing-context.md in older setups), read it before asking questions. Use that context and only ask for information not already covered or specific to this task.

Before implementing schema, understand:

Page Type - What kind of page? What's the primary content? What rich results are possible?
Current State - Any existing schema? Errors in implementation? Which rich results already appearing?
Goals - Which rich results are you targeting? What's the business value?

Core Principles

1. Accuracy First

Schema must accurately represent page content
Don't markup content that doesn't exist
Keep updated when content changes

2. Use JSON-LD

Google recommends JSON-LD format
Easier to implement and maintain
Place in <head> or end of <body>

3. Follow Google's Guidelines

Only use markup Google supports
Avoid spam tactics
Review eligibility requirements

4. Validate Everything

Test before deploying
Monitor Search Console
Fix errors promptly

Common Schema Types

Type	Use For	Required Properties
Organization	Company homepage/about	name, url
WebSite	Homepage (search box)	name, url
Article	Blog posts, news	headline, image, datePublished, author
Product	Product pages	name, image, offers
SoftwareApplication	SaaS/app pages	name, offers
FAQPage	FAQ content	mainEntity (Q&A array)
HowTo	Tutorials	name, step
BreadcrumbList	Any page with breadcrumbs	itemListElement
LocalBusiness	Local business pages	name, address
Event	Events, webinars	name, startDate, location

For complete JSON-LD examples: See references/schema-examples.md

Quick Reference

Organization (Company Page)

Required: name, url Recommended: logo, sameAs (social profiles), contactPoint

Article/BlogPosting

Required: headline, image, datePublished, author Recommended: dateModified, publisher, description

Product

Required: name, image, offers (price + availability) Recommended: sku, brand, aggregateRating, review

FAQPage

Required: mainEntity (array of Question/Answer pairs)

BreadcrumbList

Required: itemListElement (array with position, name, item)

Multiple Schema Types

You can combine multiple schema types on one page using @graph:

{
  "@context": "https://schema.org",
  "@graph": [
    { "@type": "Organization", ... },
    { "@type": "WebSite", ... },
    { "@type": "BreadcrumbList", ... }
  ]
}

Validation and Testing

Tools

Google Rich Results Test: https://search.google.com/test/rich-results
Schema.org Validator: https://validator.schema.org/
Search Console: Enhancements reports

Common Errors

Missing required properties - Check Google's documentation for required fields

Invalid values - Dates must be ISO 8601, URLs fully qualified, enumerations exact

Mismatch with page content - Schema doesn't match visible content

Implementation

Static Sites

Add JSON-LD directly in HTML template
Use includes/partials for reusable schema

Dynamic Sites (React, Next.js)

Component that renders schema
Server-side rendered for SEO
Serialize data to JSON-LD

CMS / WordPress

Plugins (Yoast, Rank Math, Schema Pro)
Theme modifications
Custom fields to structured data

Output Format

Schema Implementation

// Full JSON-LD code block
{
  "@context": "https://schema.org",
  "@type": "...",
  // Complete markup
}

Testing Checklist

Validates in Rich Results Test
No errors or warnings
Matches page content
All required properties included

Task-Specific Questions

What type of page is this?
What rich results are you hoping to achieve?
What data is available to populate the schema?
Is there existing schema on the page?
What's your tech stack?

Related Skills

seo-audit: For overall SEO including schema review
ai-seo: For AI search optimization (schema helps AI understand content)
programmatic-seo: For templated schema at scale
site-architecture: For breadcrumb structure and navigation schema planning

Gives 2 of the 12 instructions most seo skills give in ~1.0k tokens

Counted across 454 of the 460 authors here whose files we hold, read 2026-08-07

implement structured data using JSON-LDhere, and in 29 of 454, across 25 files
write unique meta descriptions under 160 charactersin 25 of 454, across 20 files
verify one H1 exists per pagein 24 of 454, across 15 files
maintain a single h1 per pagein 24 of 454, across 15 files
use JSON-LD format for all schema markupin 23 of 454, across 16 files
use descriptive anchor text for internal linksin 22 of 454, across 18 files
add descriptive alt text to imagesin 19 of 454, across 15 files
read product marketing context before auditinghere, and in 19 of 454, across 11 files
write unique title tags under 60 charactersin 19 of 454, across 14 files
add unique title and meta description per pagein 19 of 454, across 17 files
fetch robots.txt and sitemap.xmlin 19 of 454, across 18 files
Place the primary keyword in the first 100 wordsin 18 of 454, across 17 files

Said here and by no other author read

Follow Google markup guidelines and eligibility requirements
Validate markup in the Rich Results Test

Grouped from the skills themselves: near-identical wordings counted once, and counted by distinct author, so one author publishing three of these counts once. Length counted with cl100k_base; the agent that loads this file may tokenize it differently.