A two-agent quality gate for applications built with AI-assisted coding. It checks user-interface design and backend architecture against fixed, mechanically testable rules.

Use it after generating an application to check its interface and backend against Atelier’s universal rules and any applicable framework presets.

It turns broad quality expectations into pass-or-fail checks for details such as spacing, typography, contrast, credentials, and architecture.

atelier — Skill for Claude Code and Codex by anshrajore

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 anshrajore/atelier-mcp --skill atelier

Clone the repo

git clone --depth 1 https://github.com/anshrajore/atelier-mcp

Made for: Claude Code, Codex.

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/anshrajore/atelier-mcp/atelier/github.svg)](https://agentmods.dev/skills/anshrajore/atelier-mcp/atelier)

Your own site

<a href="https://agentmods.dev/skills/anshrajore/atelier-mcp/atelier"><img src="https://agentmods.dev/badge/skills/anshrajore/atelier-mcp/atelier/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/anshrajore/atelier-mcp/atelier"><img src="https://agentmods.dev/badge/skills/anshrajore/atelier-mcp/atelier.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 34 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,801 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 1 finding. 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	$0.00034	$0.01801
Opus 5	$0.00017	$0.00901
Sonnet 5	$0.00007	$0.00360
Haiku 4.5	$0.00003	$0.00180

Measured 9d ago against content hash 10742b771098, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

atelier scanned grade A with 1 finding 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 9d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- **check:** `ast: CallExpression(name in ['fetch', 'axios.get', 'axios.post', 'http.request']) -> if !has_property('timeout') and !has_property('signal') -> fail`

skills/atelier/SKILL.md · 96 lines

How it starts

The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Atelier Canonical Ruleset (Base)

Atelier Base defines universal, gradeable quality gate rules that apply across any stack. Every rule contains an absolute pass/fail threshold and a mechanical check: specification for automated evaluation without subjective interpretation.

1. Universal UI/UX Rules (`BASE-UI-xxx`)

`BASE-UI-101: Harmonic Spacing System Discipline`

Statement: All layout margins, paddings, and container gaps must strictly conform to an 8px harmonic grid (subgrid: 4px).
Threshold: Zero occurrences of spacing values outside [0, 4, 8, 12, 16, 24, 32, 48, 64, 96, 128]px.
Violation Example: margin-top: 13px; or padding: 7px 19px; or p-[17px].
check: regex: (?:(?:margin|padding|gap|top|bottom|left|right)(?:-(?:top|bottom|left|right|x|y))?\s*:\s*(\d+)px|(?:m|p|gap)-?\[(\d+)px\]) -> extract integer $1 or $2 -> fail if num % 4 != 0 or num not in [0,4,8,12,16,24,32,48,64,96,128]

`BASE-UI-102: Strict Typographic Scale & Optical Tracking`

Statement: Font sizes must derive from a standardized modular scale, with negative tracking on display text (>=24px) and wide tracking on micro-labels (<=12px uppercase).
Threshold: Font size values must belong to {12, 14, 16, 18, 20, 24, 30, 36, 48, 60, 72}px. Display headers (>=24px) must have letter-spacing <= -0.015em.
Violation Example: font-size: 29px; or font-size: 36px; letter-spacing: normal;.
check: ast: CSS/JSX TextStyleNode -> where fontSize >= 24px and letterSpacing not in ['-0.02em', '-0.025em', '-0.03em', '-0.04em', 'tracking-tight', 'tracking-tighter'] -> fail

`BASE-UI-103: WCAG 2.1 AA Contrast Minimum`

Statement: Body text and interactive icons must maintain a minimum contrast ratio of 4.5:1 against their rendered background (3.0:1 for text >= 24px).
Threshold: Calculated relative luminance contrast ratio < 4.5:1 for regular text (<24px) or < 3.0:1 for large text (>=24px) is a hard failure.
Violation Example: Text #94a3b8 (Slate-400) on white #ffffff background (contrast ratio: 2.45:1).
check: metric: contrast_ratio(foreground_color, background_color) -> fail if (is_large_text ? ratio < 3.0 : ratio < 4.5)

Read the full file on GitHub · 96 lines

Files

What ships with it

2 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.

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.

9d ago First seen · 96 lines · 34 tokens per session scan A 10742b771098

Subscribe to this mod's changes

atelier is a skill published in the GitHub repository anshrajore/atelier-mcp (0 stars, last pushed 22d ago), licensed MIT. It adds 34 tokens to every session and 1,801 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Code review Design and UX mcp mcp-client mcp-server mcp-servers mcp-tools npm

atelier

Getting it into your agent

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Makes network callslowCapability

How it starts

Atelier Canonical Ruleset (Base)

1. Universal UI/UX Rules (`BASE-UI-xxx`)

`BASE-UI-101: Harmonic Spacing System Discipline`

`BASE-UI-102: Strict Typographic Scale & Optical Tracking`

`BASE-UI-103: WCAG 2.1 AA Contrast Minimum`

What ships with it

What this file has done since we first saw it

Other skills, from other repositories

interactive-ui

pr-analysis

pr-review

issue-management

release-management

error-handling

atelier

Getting it into your agent

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Makes network callslowCapability

How it starts

Atelier Canonical Ruleset (Base)

1. Universal UI/UX Rules (BASE-UI-xxx)

BASE-UI-101: Harmonic Spacing System Discipline

BASE-UI-102: Strict Typographic Scale & Optical Tracking

BASE-UI-103: WCAG 2.1 AA Contrast Minimum

What ships with it

What this file has done since we first saw it

Other skills, from other repositories

interactive-ui

pr-analysis

pr-review

issue-management

release-management

error-handling

1. Universal UI/UX Rules (`BASE-UI-xxx`)

`BASE-UI-101: Harmonic Spacing System Discipline`

`BASE-UI-102: Strict Typographic Scale & Optical Tracking`

`BASE-UI-103: WCAG 2.1 AA Contrast Minimum`