HTML accessibility quick check

Scans HTML for images without alt, unlabeled inputs, missing lang, heading skips, empty links and buttons, and vague link text, with line numbers and selectors.

ClaudeHermes AgentCodexCursorMIT (modify, redistribute and use commercially)Python

What it does

Reads HTML files or a built folder and lists accessibility problems that can be detected reliably by a machine.

  • Images without alt, or with a file name or a generic word as alt
  • Form fields without a label (placeholder alone is flagged)
  • Missing <html lang> or <title>
  • Heading level skips (h2 followed by h4) and pages without an h1
  • Links and buttons with no text or accessible name
  • Vague link text such as "click here", "read more" and common Japanese equivalents
  • Duplicate ids, iframes without title, positive tabindex, viewport settings that block zoom

Each finding includes file, line, column, a CSS selector and an example fix.

How to use

python scripts/a11y_check.py dist --md a11y-report.md --json a11y-report.json

The agent verifies the findings and points to the template or content that needs to change.

Requirements

  • Python 3 (standard library only)

Caveats

  • This is a quick static check, not a WCAG conformance audit.
  • Colour contrast, keyboard operation and the quality of alt text still need a human review, and the report says so.
  • Content rendered later by JavaScript is not included.

How to install

  1. Unzip the downloaded file (it contains a html-accessibility-check/ folder with SKILL.md).
  2. Copy the whole folder into your agent's skills folder.
    • Claude: ~/.claude/skills/ (per project: .claude/skills/)
    • Hermes Agent: ~/.hermes/skills/
    • Codex: ~/.agents/skills/ / Cursor: ~/.cursor/skills/
    • Claude app (claude.ai): upload the ZIP in Customize → Skills
  3. Restart the agent and check that the skill appears in its skill list.

Step-by-step install for Windows / Mac and each agent

Seller

AI Skill Market (official)

44 published skills

Seller profile and all skills