htmx Skill for Claude Code

htmx version: 2.x (built from htmx 2.0.8 documentation)

A comprehensive Claude Code skill that gives Claude deep knowledge of htmx — the library that extends HTML with attributes for AJAX, CSS transitions, WebSockets, and Server-Sent Events.

What This Skill Does

When activated, Claude gains access to:

• Complete attribute reference — all hx-* attributes with syntax, modifiers, inheritance rules, and edge cases
• 24 UI patterns — click-to-edit, infinite scroll, active search, lazy loading, inline validation, modals, tabs, file upload, sortable, progress bars, and more
• Server-side integration — working endpoint examples for Flask, Express, Django, FastAPI, Spring Boot, Go, Rails, and Laravel
• Extension guides — SSE, WebSocket, Idiomorph (DOM morphing), head-support, response-targets, preload, and how to build custom extensions
• Response handling — HTTP headers, status code configuration, OOB swaps, and the 204 vs 200 gotcha
• CSS animations — htmx lifecycle classes (htmx-swapping, htmx-settling, htmx-added) and View Transitions API

Installation

From GitHub (recommended)

git clone https://github.com/mintarasss/htmx-skill.git

Then copy the htmx/ folder into your Claude Code skills directory:

# Global (available in all projects)
cp -r htmx-skill/htmx ~/.claude/skills/htmx

# Project-specific (only this project)
mkdir -p .claude/skills
cp -r htmx-skill/htmx .claude/skills/htmx

One-liner

# Global
git clone https://github.com/mintarasss/htmx-skill.git /tmp/htmx-skill && cp -r /tmp/htmx-skill/htmx ~/.claude/skills/htmx && rm -rf /tmp/htmx-skill

# Project-specific
git clone https://github.com/mintarasss/htmx-skill.git /tmp/htmx-skill && mkdir -p .claude/skills && cp -r /tmp/htmx-skill/htmx .claude/skills/htmx && rm -rf /tmp/htmx-skill

After installing, restart Claude Code or run /reload-plugins.

When It Activates

The skill triggers automatically when you:

• Work with any hx-* attributes
• Ask about htmx by name
• Build hypermedia-driven / HTML-over-the-wire applications
• Implement patterns like live search, inline editing, infinite scroll
• Write server endpoints that return HTML fragments
• Ask about adding interactivity to server-rendered pages without a JS framework

Skill Structure

htmx/
├── SKILL.md                        # Main skill (core concepts, attributes, patterns)
├── evals/
│   └── evals.json                  # Test cases and assertions
└── references/
    ├── attributes.md    # Complete attribute reference with all options
    ├── patterns.md      # 24 UI patterns with full HTML + server code
    ├── extensions.md    # SSE, WebSocket, Idiomorph, preload, etc.
    └── server-side.md   # Server integration, headers, framework examples

The skill uses progressive disclosure — the main SKILL.md (~320 lines) covers the most common attributes and patterns. Reference files are consulted only when deeper detail is needed, keeping context usage efficient.

Examples

Here are some things you can ask Claude with this skill active:

“Add a live search to my contacts page with debouncing. I’m using Flask.”

“How do I delete a table row with a fade-out animation and confirmation dialog?”

“I need inline email validation that checks the server as the user types, plus OOB updates to a contacts table on form submit. Using Express.js.”

“Set up Server-Sent Events to push notifications to the page in real time.”

“What’s the difference between hx-swap-oob and hx-select-oob? When should I use each?”

What Makes This Skill Good

• Working code, not just rules — every pattern includes complete HTML and server-side code you can copy and run
• Covers edge cases — the 204 vs 200 gotcha, `` wrapping for OOB table rows, GET excluding form values, body targeting quirk
• Framework-agnostic server examples — Flask, Express, Django, FastAPI, Spring Boot, Go, Rails, and Laravel
• Full extension coverage — SSE, WebSocket, Idiomorph, head-support, response-targets, preload
• Inheritance documentation — which attributes inherit and which don’t, plus hx-disinherit/hx-inherit controls

Built From Official Documentation

This skill covers htmx 2.x (specifically built from the 2.0.8 documentation). If you’re working with htmx 1.x, note that some attributes and behaviors differ — the htmx 1 compatibility extension can help bridge the gap.

It was built by thoroughly reading and distilling the official htmx documentation, including:

• Core documentation (docs.md)
• All 35 attribute reference pages
• 25 example pages with patterns
• JavaScript API reference
• Events reference
• Extension documentation (SSE, WS, Idiomorph, head-support, response-targets, preload)
• Server-side integration examples
• Response headers documentation
• Quirks and gotchas page

Contributing

Contributions are welcome! If you find an htmx pattern or edge case that’s missing, please open a PR.

License

MIT