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.
npx skills add xrnavigation/web-a11y-plugin --skill hostile-pattern-detectiongit clone --depth 1 https://github.com/xrnavigation/web-a11y-pluginWrote 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/xrnavigation/web-a11y-plugin/hostile-pattern-detection)<a href="https://agentmods.dev/skills/xrnavigation/web-a11y-plugin/hostile-pattern-detection"><img src="https://agentmods.dev/badge/skills/xrnavigation/web-a11y-plugin/hostile-pattern-detection/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/xrnavigation/web-a11y-plugin/hostile-pattern-detection"><img src="https://agentmods.dev/badge/skills/xrnavigation/web-a11y-plugin/hostile-pattern-detection.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00077 | $0.03747 |
| Opus 5.5 | $0.00031 | $0.01499 |
| Sonnet 5.5 | $0.00015 | $0.00749 |
| Haiku 4.5 | $0.00008 | $0.00375 |
Grade A, and why
hostile-pattern-detection 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 1mo 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.
The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
What ships with it
4 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.
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.
- 1mo ago First seen · 190 lines · 77 tokens per session scan A 12567c8f7ded
hostile-pattern-detection is a skill published in the GitHub repository xrnavigation/web-a11y-plugin (1 stars, last pushed 13d ago), with no licence file. It adds 77 tokens to every session and 3,747 once invoked, about $0.0003 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.
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…
kb-design-system
Reference data, not a reviewer. Validate design system tokens for WCAG AA/AAA contrast. Compute color token contrast, focus ring validation (WCAG 2.4.13), motion tokens, and spacing for touch targets across frameworks.
kb-cognitive-accessibility
Reference data, not a reviewer. Review UI for cognitive load, plain language clarity, and WCAG 2.2 cognitive SC (3.3.7, 3.3.8, 3.3.9). Includes COGA guidance, reading level, auth patterns, and timeout warnings.
powerpoint-accessibility
Scan and fix .pptx files: slide titles, alt text and reading order.
kb-data-visualization-accessibility
Reference data, not a reviewer. Audit charts and graphs for accessibility: SVG ARIA, data table alternatives, keyboard interaction, color-safe palettes, and library APIs.
alt-text-headings
Alt text, SVGs, figures, charts, heading order, page titles and landmarks.