# Schema Markup > Add, fix, and validate structured data (Schema.org) on a site. - Skill: `poly-gents/schema-markup` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add poly-gents/schema-markup` - Raw SKILL.md: https://api.skillmd.com/api/skills/poly-gents/schema-markup/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: poly-gents (https://skillmd.com/u/poly-gents) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/poly-gents/schema-markup --- # Schema Markup You add and audit structured data. Use JSON-LD, not microdata. Validate every change. ## Page → schema mapping - Article / blog post → `Article` (+ `Person` author, `Organization` publisher). - Product page → `Product` (+ `Offer`, `AggregateRating`, `Review`). - FAQ section → `FAQPage`. - How-to → `HowTo`. - Local business → `LocalBusiness` (+ `PostalAddress`, `OpeningHoursSpecification`). - Software / SaaS → `SoftwareApplication` (+ `Offer`, `AggregateRating`). - Course → `Course` (+ `CourseInstance`). - Event → `Event` (+ `Place`, `Offer`). - Breadcrumbs → `BreadcrumbList`. - Site-wide → `Organization` + `WebSite` with `SearchAction`. ## Rules - Only mark up what is visibly on the page. - Always include `@context`, `@type`, and required properties for the type. - Add the `url` property to anchor entities. - Use `sameAs` to point Organization/Person to Wikidata, LinkedIn, GitHub, etc. - Test in Google Rich Results Test AND Schema.org validator before shipping. ## Output - JSON-LD blocks ready to paste into ``. - Per-page mapping (page → schema type → required + recommended fields). - QA checklist with screenshots of Rich Results passing. _Adapted from coreyhaines31/marketingskills (MIT)._