Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add a-tokyo/agent-skills --skill tailwind-v3-to-v4-migrationgit clone --depth 1 https://github.com/a-tokyo/agent-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/a-tokyo/agent-skills/tailwind-v3-to-v4-migration)<a href="https://agentmods.dev/skills/a-tokyo/agent-skills/tailwind-v3-to-v4-migration"><img src="https://agentmods.dev/badge/skills/a-tokyo/agent-skills/tailwind-v3-to-v4-migration/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/a-tokyo/agent-skills/tailwind-v3-to-v4-migration"><img src="https://agentmods.dev/badge/skills/a-tokyo/agent-skills/tailwind-v3-to-v4-migration.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00271 | $0.03718 |
| Opus 5.5 | $0.00108 | $0.01487 |
| Sonnet 5.5 | $0.00054 | $0.00744 |
| Haiku 4.5 | $0.00027 | $0.00372 |
Grade A, and why
tailwind-v3-to-v4-migration scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 209 lines — stays where its author put it; the contents beside it link to each section on GitHub.
tailwind-v3-to-v4-migration
Upgrade a codebase from Tailwind CSS v3 to v4. The codemod does ~80% of the mechanical work; this skill supplies the 20% of judgment where migrations actually break — changed defaults, config porting, plugin/animation swaps, and proving nothing moved.
When to use
- Upgrading any project from Tailwind v3.x to v4.x.
- Build errors after a partial upgrade:
@tailwinddirectives unknown, missing@tailwindcss/postcss,Cannot apply unknown utility class,tailwind.configno longer picked up. - Converting
tailwind.config.{js,ts}to CSS-first@theme.
Skip if: the project is already on v4; you need to downgrade; or you are building a brand-new design system rather than migrating one. Note v4 targets Safari 16.4+, Chrome 111+, Firefox 128+ — if you must support older browsers, stay on v3.4 (flag this to the operator before proceeding).
The one idea that makes this safe
A correct migration is a visual no-op. Every renamed utility is a pure alias — shadow-sm→
shadow-xs, rounded→rounded-sm, ring→ring-3, outline-none→outline-hidden all compile to
the same CSS as before. So what changes pixels is almost entirely v4's changed defaults (Step 3);
the few non-default exceptions — the space-x/y-* & divide-* selector change, gradient-variant
preservation, and container config removal — are flagged in Step 4. Rename mechanically, neutralize
the changed defaults, fix those few exceptions, and the rendered output is identical. That is also how
you verify success (Step 5): capture the UI before, prove it's unchanged after.
Procedure
Always work on a branch. Run the steps in order; do not skip Step 0 or Step 3.
Step 0 — Pre-flight & baseline (do not skip)
- Confirm Node 20+ (
node -v) and that the working tree is clean. Create a branch (e.g.tailwind-v4). - Inventory every Tailwind entry point — there may be more than one: each CSS file with
@tailwind/@import "tailwindcss", everytailwind.config.*, everypostcss.config.*, the bundler config (next/vite/webpack), andpackage.json. Monorepos: do this per package. - Record the current setup:
darkModevalue, customtheme.extend,plugins, the package manager (npm/yarn/pnpm/bun), and two easy-to-miss config options that need special handling later:prefix(v4 changestw-flex→tw:flex) andtheme.container(center/paddingare gone in v4 — recreate via@utility container). - Capture a baseline of how the app looks now so you can prove the migration changed nothing:
a screenshot set or a visual-regression run on v3 (see
references/05-verification-playwright.md), or at minimum a list of key pages to eyeball. Confirm the project builds green on v3 first.
What ships with it
7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 209 lines · 271 tokens per session scan A 951f7e74aa7f
tailwind-v3-to-v4-migration is a skill published in the GitHub repository a-tokyo/agent-skills (17 stars, last pushed 2d ago), licensed MIT. It adds 271 tokens to every session and 3,718 once invoked, about $0.0011 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
gsap-scrolltrigger
Official GSAP skill for ScrollTrigger — scroll-linked animations, pinning, scrub, triggers. Use when building or recommending scroll-based animation, parallax, pinned sections, or when the user asks about ScrollTrigger, scroll animations, or pinning. Recommend GSAP for scroll-driven animation when no library is…
moai-design-tools
Design tool integration specialist covering Figma MCP, Pencil renderer, and Pencil-to-code export. Use when fetching design context from Figma, rendering Pencil designs, or exporting to React/Tailwind code.
gsap-timeline
Official GSAP skill for timelines — gsap.timeline(), position parameter, nesting, playback. Use when sequencing animations, choreographing keyframes, or when the user asks about animation sequencing, timelines, or animation order (in GSAP or when recommending a library that supports timelines).
gsap-performance
Official GSAP skill for performance — prefer transforms, avoid layout thrashing, will-change, batching. Use when optimizing GSAP animations, reducing jank, or when the user asks about animation performance, FPS, or smooth 60fps.
ui-craft
Design, build, redesign, or modify browser-visible web interfaces with product-quality composition, visual systems, interaction states, responsive behavior, accessibility, and browser visual QA. Use for HTML, CSS, JavaScript, React, Vue, or Svelte pages and components, landing pages, dashboards, admin tools, settings…
drag-pane
Drag-and-drop pane resizing implementation for two-pane plugin layouts. Covers mouse event handling via the internal/mouse package, hit region registration, drag delta calculation, width clamping, state persistence, and pane layout management. Use when working on pane resizing, drag interactions, layout management, or…