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 MichelKerkmeester/skilled-agent-harness_spec-driven-loops --skill shadcngit clone --depth 1 https://github.com/MichelKerkmeester/skilled-agent-harness_spec-driven-loopsWrote 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/michelkerkmeester/skilled-agent-harness_spec-driven-loops/shadcn)<a href="https://agentmods.dev/skills/michelkerkmeester/skilled-agent-harness_spec-driven-loops/shadcn"><img src="https://agentmods.dev/badge/skills/michelkerkmeester/skilled-agent-harness_spec-driven-loops/shadcn/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/michelkerkmeester/skilled-agent-harness_spec-driven-loops/shadcn"><img src="https://agentmods.dev/badge/skills/michelkerkmeester/skilled-agent-harness_spec-driven-loops/shadcn.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 | $0.00090 | $0.04499 |
| Opus 5 | $0.00045 | $0.02250 |
| Sonnet 5 | $0.00018 | $0.00900 |
| Haiku 4.5 | $0.00009 | $0.00450 |
Grade A, and why
shadcn 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 7d 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.
This is a copy
92% identical to shadcn — 25 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 261 lines — stays where its author put it; the contents beside it link to each section on GitHub.
shadcn/ui
A framework for building ui, components and design systems. Components are added as source code to the user's project via the CLI.
IMPORTANT: Run all CLI commands using the project's package runner:
npx shadcn@latest,pnpm dlx shadcn@latest, orbunx --bun shadcn@latest— based on the project'spackageManager. Examples below usenpx shadcn@latestbut substitute the correct runner for the project.
Current Project Context
!`npx shadcn@latest info --json`
The JSON above contains the project config and installed components. Use npx shadcn@latest docs <component> to get documentation and example URLs for any component.
Principles
- Use existing components first. Use
npx shadcn@latest searchto check registries before writing custom UI. Check community registries too. - Compose, don't reinvent. Settings page = Tabs + Card + form controls. Dashboard = Sidebar + Card + Chart + Table.
- Use built-in variants before custom styles.
variant="outline",size="sm", etc. - Use semantic colors.
bg-primary,text-muted-foreground— never raw values likebg-blue-500.
Critical Rules
These rules are always enforced. Each links to a file with Incorrect/Correct code pairs.
Styling & Tailwind → styling.md
classNamefor layout, not styling. Never override component colors or typography.- No
space-x-*orspace-y-*. Useflexwithgap-*. For vertical stacks,flex flex-col gap-*. - Use
size-*when width and height are equal.size-10notw-10 h-10. - Use
truncateshorthand. Notoverflow-hidden text-ellipsis whitespace-nowrap. - No manual
dark:color overrides. Use semantic tokens (bg-background,text-muted-foreground). - Use
cn()for conditional classes. Don't write manual template literal ternaries. - No manual
z-indexon overlay components. Dialog, Sheet, Popover, etc. handle their own stacking.
Forms & Inputs → forms.md
What ships with it
12 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.
- 7d ago First seen · 261 lines · 90 tokens per session scan A c5a5c3a8e380
shadcn is a skill published in the GitHub repository MichelKerkmeester/skilled-agent-harness_spec-driven-loops (35 stars, last pushed today), licensed MIT. It adds 90 tokens to every session and 4,499 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. It is 92% identical to shadcn, differing in 25 lines, and is treated as a copy.
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