mastra: Skill for Claude Code

.claude/skills/tailwind-v4/SKILL.md

tailwind-v4 is a skill for Claude Code from mastra-ai/mastra. It costs 67 tokens per session (2,364 once invoked), scanned A, original, no licence file.

A guide for writing, reviewing, and updating Tailwind CSS, a tool that provides ready-made styling classes for websites. It covers Tailwind version 4 and changes from version 3.

In plain words
What is it for?
Use it when working with Tailwind classes, @theme blocks, CSS-first configuration, or older version 3 syntax.
Why use it?
It helps avoid mixing old Tailwind syntax with the newer version or configuring version 4 incorrectly. It also gives the agent guidance when changing Tailwind code.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is mastra-ai/mastra's own configuration. It tells Claude Code how to work on mastra itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything mastra configures →

Reuse

Borrowing it

Nothing to install: this file belongs to mastra-ai/mastra. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/mastra-ai/mastra/main/.claude/skills/tailwind-v4/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/mastra-ai/mastra

Made for: Claude Code.

Wrote 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.

agentmods badge for tailwind-v4

README.md
[![agentmods](https://agentmods.dev/badge/skills/mastra-ai/mastra/tailwind-v4/github.svg)](https://agentmods.dev/skills/mastra-ai/mastra/tailwind-v4)
Your own site
<a href="https://agentmods.dev/skills/mastra-ai/mastra/tailwind-v4"><img src="https://agentmods.dev/badge/skills/mastra-ai/mastra/tailwind-v4/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.

agentmods 80×15 button for tailwind-v4

Your own site · 80×15
<a href="https://agentmods.dev/skills/mastra-ai/mastra/tailwind-v4"><img src="https://agentmods.dev/badge/skills/mastra-ai/mastra/tailwind-v4.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 67 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,364 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 3 findings, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Prompt Injection · line 59
    Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.
    Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
  • medium Prompt Injection · line 62
    Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.
    Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
  • medium Prompt Injection · line 63
    Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.
    Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
How audits are shown
Origin unknown No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00067 $0.02364
Opus 5 $0.00034 $0.01182
Sonnet 5 $0.00013 $0.00473
Haiku 4.5 $0.00007 $0.00236

Measured 12d ago against content hash d89c363a727e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

tailwind-v4 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 12d 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.

.claude/skills/tailwind-v4/SKILL.md · 115 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Changes

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.

  1. 12d ago First seen · 115 lines · 67 tokens per session scan A d89c363a727e

Subscribe to this mod's changes

tailwind-v4 is a skill published in the GitHub repository mastra-ai/mastra (27,953 stars, last pushed today), with no licence file. It adds 67 tokens to every session and 2,364 once invoked, about $0.0003 per session on Opus 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.

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