HTML Coder Skill

Expert skill for professional HTML development with focus on semantic markup, accessibility, HTML5 features, and standards-compliant web content.

When to Use This Skill

• Creating HTML documents with semantic structure
• Building accessible forms with HTML5 validation
• Implementing responsive markup and multimedia
• Using HTML5 APIs (Canvas, SVG, Storage, Geolocation)
• Troubleshooting validation or accessibility issues

OpenSquilla Webpage Delivery

For a new runnable webpage when workspace file-authoring tools are available:

1. Create a filesystem-safe, dedicated project subdirectory such as webpage-<topic-slug>/; never place a generated site directly in the workspace root.
2. Keep index.html, local CSS/JavaScript, and every local asset inside that project root, using browser-relative references.
3. Validate the finished project, then call open_workspace_preview with the entry file and the complete dedicated root:

{
  "path": "webpage-<topic-slug>/index.html",
  "bundle": "directory",
  "bundle_root": "webpage-<topic-slug>"
}

Do not bundle the entire workspace. When a caller explicitly requests source-only output, forbids tool calls, or supplies its own deterministic writer, follow that narrower caller contract instead. When file authoring or open_workspace_preview is unavailable, return only the requested guidance or source and do not claim that a runnable project was opened.

Core Capabilities

• Semantic HTML: Document structure, content sections, accessibility-first markup
• Forms: All input types, validation attributes, fieldsets, labels
• Media: Responsive images, audio/video, Canvas, SVG
• HTML5 APIs: Web Storage, Geolocation, Drag & Drop, Web Workers
• Accessibility: ARIA, screen reader support, WCAG compliance

Essential References

Core documentation for HTML experts: