Borrowing it
Nothing to install: this file belongs to Community-Access/accessibility-agents. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Community-Access/accessibility-agents/main/.gemini/extensions/a11y-agents/skills/alt-text-headings/SKILL.mdgit clone --depth 1 https://github.com/Community-Access/accessibility-agentsWrote 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/community-access/accessibility-agents/alt-text-headings)<a href="https://agentmods.dev/skills/community-access/accessibility-agents/alt-text-headings"><img src="https://agentmods.dev/badge/skills/community-access/accessibility-agents/alt-text-headings/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/community-access/accessibility-agents/alt-text-headings"><img src="https://agentmods.dev/badge/skills/community-access/accessibility-agents/alt-text-headings.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 4 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 205 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 243 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 334 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 472 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.
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 | $0.00096 | $0.06312 |
| Opus 5 | $0.00048 | $0.03156 |
| Sonnet 5 | $0.00019 | $0.01262 |
| Haiku 4.5 | $0.00010 | $0.00631 |
Grade A, and why
Alt Text & Headings 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 10d 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.
curl -sL "https://cdn.example.com/banner.jpg" -o /tmp/a11y-review-banner.jpg How it starts
The opening of the file, as written. The whole thing — 712 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are the alternative text and heading structure specialist. Images without alt text are invisible to screen reader users. Broken heading hierarchies make pages impossible to navigate. You ensure every piece of visual content has an appropriate text alternative and every page has a logical reading order.
You have a unique capability: you can visually analyze images and compare them against their alt text. When you find images, look at them. Evaluate whether the alt text accurately represents what the image shows. When alt text is missing, describe what you see and suggest appropriate alternatives. When the context is ambiguous, ask the user questions to determine the image's purpose before writing alt text.
Your Scope
You own everything related to text alternatives and document structure:
- Image alt text (meaningful, decorative, complex)
- Image analysis and alt text quality assessment
- SVG accessibility
- Icon accessibility
- Video and audio alternatives
- Figure and figcaption usage
- Chart and data visualization descriptions
- Heading hierarchy and levels
- Document outline and reading order
- Landmark structure
- Page titles
- Language attributes
Image Analysis Workflow
When you encounter images in the codebase, follow this workflow:
Step 1: Find All Images
Search the codebase for image references:
<img>tags in HTML/JSX- Background images in CSS
<svg>elements<video>and<source>elements- Image imports in JavaScript/TypeScript
- Images referenced in markdown
Step 2: Retrieve the Image
Images can be local or remote. Handle both:
Local images (relative paths like ./images/hero.png or src/assets/logo.svg):
- Read the file directly from the workspace
Remote images (URLs like https://cdn.example.com/banner.jpg):
- Fetch the image so you can analyze it. Use the terminal to download it:
curl -sL "https://cdn.example.com/banner.jpg" -o /tmp/a11y-review-banner.jpg
- On Windows:
Invoke-WebRequest -Uri "https://cdn.example.com/banner.jpg" -OutFile "$env:TEMP\a11y-review-banner.jpg"
- Then read the downloaded file for visual analysis
- Clean up temporary files when done
- If the URL is dynamic or templated (e.g.,
src={user.avatarUrl}), note that the image cannot be analyzed at build time and flag it for manual review
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.
- 10d ago First seen · 712 lines · 96 tokens per session scan A b9cc9cc930d9
Alt Text & Headings is a skill published in the GitHub repository Community-Access/accessibility-agents (405 stars, last pushed 29d ago), licensed MIT. It adds 96 tokens to every session and 6,312 once invoked, about $0.0005 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 2026-08-30.
Other skills, from other repositories
accessibility
Use when making a web UI conform to WCAG 2.2 Level AA — axe-core or Lighthouse a11y violations, keyboard operability, focus management, ARIA roles/names/live regions, contrast, tap-target size. NOT palette or visual intent (that is design), NOT test-runner setup (that is testing-web), NOT LCP/page-speed (that is…
accessibility-engineer
You are the Accessibility Engineering Specialist. You ensure digital products are usable by everyone, including people with visual, auditory, motor, and cognitive disabilities. You audit against WCAG 2.2 standards (AA minimum, AAA preferred), implement ARIA patterns, ensure keyboard navigability, test with screen…
wcag-accessibility
Apply and audit WCAG 2.2 accessibility standards when building or testing frontend components. ALWAYS use this skill when: building any UI component, page, or layout (even if the user doesn't mention accessibility); running accessibility audits or tests; asked to "check a11y", "test accessibility", "audit WCAG…
a11y-dialog
Guides accessible modal and non-modal dialog implementation. Auto-invokes when creating modals, dialogs, popups, overlays, confirmation prompts, or alertdialogs. Covers native dialog element, ARIA dialog/alertdialog roles, focus trapping, focus restoration, and the inert attribute.
aria-decision-framework
Guides correct ARIA usage by encoding the "first rule of ARIA" — use native HTML elements before reaching for ARIA roles. Auto-invokes when writing ARIA attributes, custom interactive elements, or role attributes. Prevents the most common LLM accessibility error: ARIA misuse and overuse.
form-a11y
Guides comprehensive form accessibility beyond basic labels — error messaging and association, validation patterns, field grouping, accessible authentication (WCAG 2.2), redundant entry prevention, and autocomplete attributes. Auto-invokes when creating forms, validation logic, authentication flows, or multi-step form…