Design vs Testing · both proven

ui-styling vs writing-guidelines

Both skills were run through Claude twice: once on a fixed brief without the skill, once with it. The briefs differ because each is written for the job the skill claims to do, so compare each skill against its own baseline, then decide which difference matters for your work. They are in different categories, so this is a choice of job, not a head-to-head on the same job.

ui-styling

Create beautiful, accessible user interfaces with shadcn/ui components (built on Radix UI + Tailwind), Tailwind CSS utility-first styling, and canvas-based visual designs. Use when building user interfaces, implementing design systems, creating responsive layouts, adding accessible components (dialogs, dropdowns, forms, tables), customizing themes and colors, implementing dark mode, generating…

Category: Design
Source: nextlevelbuilder/ui-ux-pro-max-skill
License: MIT
Proof model: claude-opus-5-5
Brief: “Build the main screen of Quayside, an internal tool a small logistics company uses to track container shipments: a sidebar, a filter bar, a table of 12 shipments with status, ETA and port, a detail panel for the selected shipment with a timeline, and an empty state for when filters match nothing. Make it accessible and keyboard friendly.”
Skill commit: d14efff

Without the skillWith ui-styling

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Without, runWith ui-styling, run3 independent runs per side, none selected by hand.

Download the with-skill page

writing-guidelines

Review docs/prose for Writing Guidelines compliance. Use when asked to "review my docs", "check writing style", "audit prose", "review docs voice and tone", or "check this page against the writing handbook".

Category: Testing
Source: vercel-labs/agent-skills
License: Not stated
Proof model: claude-opus-5-5
Brief: “Review and rewrite this getting-started page for Pipewell, a data pipeline CLI. The draft opens with two paragraphs of company history, mixes 'you' and 'the user', buries the install command in the fourth paragraph, uses passive voice throughout, and ends without a next step. Write the improved page as a single HTML document, followed by a short list of what you changed and why.”
Skill commit: 063bee9

Without the skillWith writing-guidelines

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Without, runWith writing-guidelines, run3 independent runs per side, none selected by hand.

Download the with-skill page

We don’t pick a winner for you: the pages are the evidence. Both proofs can be repeated with the brief, model and commit shown above. See alternatives to ui-styling or alternatives to writing-guidelines.