A required set of 21 design rules for generated frontend interfaces, covering typography, colours, spacing, motion, and related visual details. It applies when producing HTML, CSS, or JavaScript user interfaces.

Use it when creating or reviewing frontend code and when running the listed audit, normalisation, hardening, polishing, or critique checks.

It gives UI-generating work consistent constraints to check against, such as readable text sizes, regular spacing, and accessible visual choices.

impeccable — Skill for Claude Code by dnsatgit/aigod

Install

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.

Any agent

npx skills add dnsatgit/aigod --skill impeccable

Clone the repo

git clone --depth 1 https://github.com/dnsatgit/aigod

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/dnsatgit/aigod/impeccable/github.svg)](https://agentmods.dev/skills/dnsatgit/aigod/impeccable)

Your own site

<a href="https://agentmods.dev/skills/dnsatgit/aigod/impeccable"><img src="https://agentmods.dev/badge/skills/dnsatgit/aigod/impeccable/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/dnsatgit/aigod/impeccable"><img src="https://agentmods.dev/badge/skills/dnsatgit/aigod/impeccable.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 18 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 695 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.

Origin original 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.

Model	Per session	Once invoked
Fable 5.1	$0.00018	$0.00695
Opus 5.5	$0.00007	$0.00278
Sonnet 5.5	$0.00004	$0.00139
Haiku 4.5	$0.00002	$0.00069

Measured 2mo ago against content hash 45e6b45fd416, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

impeccable 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 2mo 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/impeccable/SKILL.md · 91 lines

How it starts

The opening of the file, as written. The whole thing — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Impeccable Frontend Constraint Layer

This is NOT an optional skill — it is a mandatory constraint applied to all frontend output. Any sub-agent or skill producing HTML, CSS, or JavaScript UI code must comply.

Based on: https://github.com/pbakaus/impeccable

Enforcement

When any agent produces frontend code, this constraint layer is automatically loaded. The output must pass the audit pipeline:

/audit → /normalize → /harden → /polish → /critique

The 7 Standards

1. Typography

No Inter, Roboto, or system-ui defaults without explicit justification
Modular type scale (e.g., 1.25 ratio)
16px minimum body text
Line height: 1.4-1.6 for body, 1.1-1.2 for headings
Max line length: 65-75 characters

2. Color (OKLCH)

Use OKLCH color space, not hex/rgb/hsl
Tinted neutrals — no pure gray (#808080)
60-30-10 color ratio (dominant-secondary-accent)
Semantic color tokens (not raw values in components)

3. Spatial System (4pt base)

All spacing values are multiples of 4px
Use gap over margin for component spacing
Container queries over media queries where supported
Consistent padding scale

4. Motion

Meaningful transitions only — no decorative animation
Respect prefers-reduced-motion
Duration: 150-300ms for micro-interactions, 300-500ms for layout shifts
No bounce easing, no elastic effects

5. Interaction

44px minimum touch targets
Visible focus indicators (not just outline: none)
Hover states that also work on touch
Loading states for async operations

6. Responsive

Mobile-first approach
Fluid typography with clamp()
Logical CSS properties (margin-inline, padding-block)
i18n budget: 30-40% extra space for translated text

7. Accessibility

WCAG AA minimum: 4.5:1 contrast for body text, 3:1 for large text and UI
Semantic HTML elements
ARIA labels only when semantic HTML is insufficient
Screen reader testing checklist

Anti-Patterns (Auto-Fail)

Any of these in the output = automatic failure:

Read the full file on GitHub · 91 lines

Files

What ships with it

1 file 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.

references/.gitkeep 0 B

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.

2mo ago First seen · 91 lines · 18 tokens per session scan A 45e6b45fd416

Subscribe to this mod's changes

impeccable is a skill published in the GitHub repository dnsatgit/aigod (2 stars, last pushed 7mo ago), licensed MIT. It adds 18 tokens to every session and 695 once invoked, about $0.0001 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 2026-08-31.

CSS and styling Design and UX Frontend

impeccable next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
impeccablednsatgit/aigod	Skill	2	7mo ago	MIT	A	18	Claude Code
anti-slop-designsickn33/agentic-awesome-skills	Skill	49k	yesterday	MIT	A	34	Claude Code
chakra-ui-builderchakra-ui/chakra-ui	Skill	41k	yesterday	MIT	A	214	Claude Code, Codex
visual-ralphYeachan-Heo/oh-my-codex	Skill	34k	3d ago	MIT	A	52	Codex
open-design-setupcompozy/compozy	Skill	2.8k	yesterday	MIT	A	67	Claude Code, Codex
frontend-visual-qadaymade/claude-code-skills	Skill	1.5k	yesterday	MIT	A	125	Claude Code, Codex
prototype-webnexu-io/html-anything	Skill	9.4k	24d ago	Apache-2.0	A	24	Claude Code, Codex