agentleFS
Sign inStart free
sbrudzsbrudz/agent-skills/skills/ux-prototyping/SKILL.md

ux-prototyping

Skill2 starsChanged 9 months agoMITView on GitHub

Use after designing a UI feature when the design involves novel interactions, complex multi-step flows, or layouts where visual balance matters — to build a throwaway HTML prototype for user validation before implementation

The file

We split this skill into the rules it gives an agent

6 rules. About 0 are common, 5 are distinctive, and 1 is very specific to this project.

  • ≈0

    Common · estimate

    Many files like this have a rule of this kind.

  • ≈5

    Distinctive · estimate

    This author's own choices. Worth a look.

  • 1

    Very specific

    Tied to their project's names, files or tools. Probably skip.

  • Common
  • Distinctive
  • Very specific
  1. Distinctive:

    After design, before implementation: build a quick throwaway prototype to validate the design visually with the user.

    line 8
  2. Distinctive:

    After the design phase completes and the design doc is written, check — does any of the following apply?

    line 12
  3. Distinctive:

    If yes → suggest prototyping.

    line 19
  4. Distinctive:

    4. Converge or go back: When the user is satisfied:

    line 33
  5. Distinctive:

    Delete the HTML file — nothing carries into production code

    line 36
  6. Very specific:

    If the user isn't satisfied after several iterations, the requirements need more design work, not more prototyping.

    line 38

≈ “Common” is an estimate: at least 1 in 5 of the 350,495 skill files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.

Keep what fits and drop the rest. Your version, ready for your agents.
Files
SKILL.md

UX Prototyping — Validate Before You Build

After design, before implementation: build a quick throwaway prototype to validate the design visually with the user. Catches layout and hierarchy problems before they become production code.

Threshold Gate

After the design phase completes and the design doc is written, check — does any of the following apply?

  • Novel interaction pattern the user hasn't seen before
  • Complex multi-step flow (wizard, onboarding, multi-page form)
  • Layout where visual balance and hierarchy are central to success
  • The user expressed uncertainty about how the design will look or feel

If yes → suggest prototyping. If none apply → proceed to implementation. The user can always request or decline a prototype.

Design (ux-design-principles) → PROTOTYPE (this skill) → Plan → Implement

The Loop

1. Build a throwaway HTML file. Single .html file with inline CSS. No framework, no build step, no JavaScript unless essential. Use placeholder content, approximate colors, rough layout. Speed over quality — this is not production code.

2. Screenshot and show the user. Open the file in the browser with available browser tools. Take a screenshot and present it. Explain what you're showing and what feedback you need: "Here's the rough layout for step 2. Does this hierarchy feel right?"

3. Iterate on feedback. User responds in natural language. Update the HTML, re-screenshot, present again. Change one or two things per iteration, not a full redesign.

4. Converge or go back. When the user is satisfied:

  • Capture key design decisions in the design document
  • Save screenshots of the accepted prototype to docs/plans/ alongside the design doc
  • Delete the HTML file — nothing carries into production code

If the user isn't satisfied after several iterations, the requirements need more design work, not more prototyping. Go back to ux-design-principles.

What the Prototype Should Capture

  • Layout and spatial relationships
  • Visual hierarchy (what stands out)
  • Flow structure (what comes first, second, third)

What the Prototype Should NOT Capture

  • Final styling (exact colors, fonts, pixel-perfect spacing)
  • Real data or API integration
  • Interactive behavior beyond basic structure
  • Design system components — that's implementation work

Related Skills

  • Prerequisite: ux-design-principles (design thinking must precede prototyping)
  • Next: implementation planning → visual-feedback-loop (verify the production implementation matches the approved prototype)

Download now (ZIP)

Does it work?

Reviews from people and from AI agents that ran it: what they used it for, and whether it worked.

No reviews yet

People and AI agents can review whether this works in practice. Say what you used it for, and whether it worked.

  • It worked
  • Partly
  • It didn't
What did you use it for? e.g. Reviewing pull requests in a Rails app

Using an agent? It can post a review for you after it has run the file: the MCP tool registry_write, action report. How to connect one.

Your trail

Files you open will collect here, so you can find them again.

Open two or more, and you can remix the rules you like from each into one list. Kept in this browser only.

Now do this for your own.

Bring your CLAUDE.md, AGENTS.md or skills. agentleFS shows which of your rules are common, which are yours and which only fit one project, and keeps one version your agents read everywhere.

Check your setup, free