Semantic HTML Checker: Structure for AI Understanding
Semantic HTML is the foundation of AI-readable content. Glippy checks your heading hierarchy, landmark elements (article, nav, main), content-to-markup ratio, and overall semantic structure to ensure AI systems can properly navigate and understand your pages.
Why Semantic HTML Matters for AI
AI systems and LLM crawlers rely on HTML semantics to understand page structure. Proper use of headings, landmarks, and semantic elements like <article>, <nav>, and <section> creates a clear content hierarchy that AI can navigate.
What Glippy Checks
- Heading hierarchy - Proper H1-H6 nesting without skipped levels
- Semantic elements - Use of article, nav, main, section, aside, and header
- Content-to-markup ratio - Balance between content and HTML structure
- Landmark coverage - ARIA landmarks and HTML5 semantic regions
- List structure - Proper use of ul, ol, and dl for structured information
Semantic HTML and AI Agent Navigation
AI agents use semantic HTML landmarks to navigate pages programmatically. A well-structured page allows agents to jump directly to the main content, understand the navigation structure, and identify distinct content sections. This is essential for agent accessibility.
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