accessibility

accessibility is a skill for Claude Code, Codex from cosmicstack-labs/mercury-agent-skills. It costs 25 tokens per session (5,019 once invoked), scanned A, original, MIT.

A web accessibility guide covering inclusive design, ARIA attributes, WCAG requirements, and automated and human testing. Accessibility means making websites usable by people with disabilities, including those using keyboards or screen readers.

In plain words
What is it for?
Use it to plan accessible interfaces, add correct labels and keyboard behavior, review designs, and test websites against accessibility requirements.
Why use it?
It helps find and prevent barriers that automated checks alone may miss, instead of discovering them just before launch.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to plan accessible interfaces, add correct labels and keyboard behavior, review designs, and test websites against accessibility requirements.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/cosmicstack-labs/mercury-agent-skills/accessibility
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 cosmicstack-labs/mercury-agent-skills --skill accessibility
Clone the repo
git clone --depth 1 https://github.com/cosmicstack-labs/mercury-agent-skills

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.

agentmods badge for accessibility

README.md
[![agentmods](https://agentmods.dev/badge/skills/cosmicstack-labs/mercury-agent-skills/accessibility.svg)](https://agentmods.dev/skills/cosmicstack-labs/mercury-agent-skills/accessibility)
Your own site
<a href="https://agentmods.dev/skills/cosmicstack-labs/mercury-agent-skills/accessibility"><img src="https://agentmods.dev/badge/skills/cosmicstack-labs/mercury-agent-skills/accessibility.svg" alt="Measured on agentmods" height="20"></a>
Per session 25 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,019 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 high

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 →

  • high Prompt Injection · line 201
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Prompt Injection · line 238
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Prompt Injection · line 390
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
How audits are shown
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00025 $0.05019
Opus 5 $0.00013 $0.02509
Sonnet 5 $0.00005 $0.01004
Haiku 4.5 $0.00003 $0.00502

Measured 8d ago against content hash 948f0ca37577, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

accessibility 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 8d 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.

categories/design/accessibility/SKILL.md · 478 lines

How it starts

The opening of the file, as written. The whole thing — 478 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Accessibility Skill

Core Principles

1. Accessibility Is a Human Right

Digital accessibility is not a compliance checkbox — it's about ensuring everyone can use the web regardless of ability. Approximately 15% of the world's population experiences some form of disability. Building accessible products is the ethical choice, not just a legal requirement.

2. Start Early, Not as an Audit

Accessibility must be considered from the first wireframe, not discovered in a last-minute audit before launch. Retrofitting accessibility costs significantly more than building it in from the start. Include a11y in design critiques, sprint planning, and definition of done.

3. Nothing About Us Without Us

Design with, not for, people with disabilities. Test with real users who rely on assistive technologies. Automated tools catch only 30-40% of accessibility issues — human testing catches the rest. Include disabled people in your user research and usability testing.

4. Accessibility Improves UX for Everyone

Curb cuts benefit everyone, not just wheelchair users. Captions help people in noisy environments. High contrast helps on sunny days. Keyboard navigation helps power users. Accessibility features often become mainstream UX improvements.

5. Progress Over Perfection

Level AAA compliance is aspirational and not always achievable. Level AA is the practical target for most products. Don't let perfect be the enemy of good — ship AA-compliant work and document remaining issues for future iterations.

Accessibility Maturity Model

Level 1: Unaware

Accessibility is not considered at all. No guidelines, no testing, no training. Accessibility issues are found only when legal complaints arise. This is the starting point — and a liability.

Level 2: Reactive

Accessibility is addressed reactively — when a bug is filed, an audit is demanded, or a legal threat emerges. Fixes are firefighting exercises. No systemic improvements occur. Burnout is high among any team members advocating for a11y.

Read the full file on GitHub · 478 lines

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. 8d ago First seen · 478 lines · 25 tokens per session scan A 948f0ca37577

Subscribe to this mod's changes

accessibility is a skill published in the GitHub repository cosmicstack-labs/mercury-agent-skills (471 stars, last pushed 13d ago), licensed MIT. It adds 25 tokens to every session and 5,019 once invoked, about $0.0001 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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