# Broken HTML

> Use when auditing metadata, crawlability, structured data, or indexability related to Fix malformed HTML structure. Verify the rendered HTML and HTTP response rather than relying only on source files.

- Skill: `thedaviddias/broken-html` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add thedaviddias/broken-html`
- Raw SKILL.md: https://api.skillmd.com/api/skills/thedaviddias/broken-html/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: thedaviddias (https://skillmd.com/u/thedaviddias)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/thedaviddias/broken-html

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# Fix malformed HTML structure

Malformed HTML can cause rendering issues across browsers and may prevent search engine crawlers from accurately parsing and indexing your content.

## Quick Reference

- Ensure all HTML tags are properly closed and nested according to specifications
- Remove stray tags or unescaped characters from the source code
- Verify the document structure follows a logical hierarchy with valid head and body sections

## Check

Validate the HTML structure of the page to identify any unclosed tags, incorrect nesting, or structural errors.

## Fix

Correct the malformed HTML by properly closing tags and ensuring all elements are nested according to the HTML5 specification.

## Explain

Explain how significant HTML errors can impact search engine bot crawling and the accessibility of a website.

## Code Review

Review metadata generation, rendered HTML, structured data, and response headers related to Fix malformed HTML structure. Flag exact routes or templates where search-facing output violates the rule, and describe how to verify the final page output.

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For full implementation details, code examples, and framework-specific guidance,
see `references/rule.md`.

Rule page: https://frontendchecklist.io/en/rules/seo/broken-html