HTMX Skill

Use this skill for HTMX implementation and integration. Read only the reference file(s) needed for the task.

Quick Start

1. Identify the domain of the task (attributes, requests, swapping, events, patterns).
2. Open the matching file from references/.
3. Implement using HTML-first, hypermedia-driven patterns.
4. Validate that server responses return HTML fragments, not JSON.

Critical Rules

• HTMX expects HTML responses from the server, not JSON.
• Most attributes inherit to child elements. Not inherited: hx-trigger, hx-on*, hx-swap-oob, hx-preserve, hx-history-elt, hx-validate. Use hx-disinherit or unset to stop inheritance of other attributes.
• Default swap strategy is innerHTML. Always confirm the intended swap method.
• Non-GET requests automatically include the closest enclosing form’s values.
• Use hx-boost="true" for progressive enhancement — pages must work without JS.
• Escape all user-supplied content server-side to prevent XSS.
• HTMX adds/removes CSS classes during the request lifecycle — use these for transitions and indicators.
• All hx-* attributes can also be written as data-hx-* for HTML validation compliance.

Reference Map

• All hx-* attributes, values, and modifiers: references/attributes.md
• Triggers, headers, parameters, CSRF, caching, CORS: references/requests.md
• Swap methods, targets, OOB swaps, morphing, view transitions: references/swapping.md
• Events, JS API, configuration, extensions, debugging: references/events-api.md
• Common UI patterns and examples: references/patterns.md
• Cross-file index and routing: references/REFERENCE.md

Task Routing

• Adding HTMX behavior to elements -> references/attributes.md
• Configuring how/when requests fire -> references/requests.md
• Controlling where/how responses render -> references/swapping.md
• Handling events, JS interop, or config -> references/events-api.md
• Building common UI patterns (search, infinite scroll, modals, etc.) -> references/patterns.md
• Cross-cutting concerns or architecture -> references/REFERENCE.md then domain-specific files