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 peterblazejewicz/claude-plugins --skill frontend-ui-engineering-avaloniagit clone --depth 1 https://github.com/peterblazejewicz/claude-pluginsWrote 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/peterblazejewicz/claude-plugins/frontend-ui-engineering-avalonia)<a href="https://agentmods.dev/skills/peterblazejewicz/claude-plugins/frontend-ui-engineering-avalonia"><img src="https://agentmods.dev/badge/skills/peterblazejewicz/claude-plugins/frontend-ui-engineering-avalonia/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/peterblazejewicz/claude-plugins/frontend-ui-engineering-avalonia"><img src="https://agentmods.dev/badge/skills/peterblazejewicz/claude-plugins/frontend-ui-engineering-avalonia.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 | $0.00110 | $0.07294 |
| Opus 5 | $0.00055 | $0.03647 |
| Sonnet 5 | $0.00022 | $0.01459 |
| Haiku 4.5 | $0.00011 | $0.00729 |
Grade C, and why
frontend-ui-engineering-avalonia scanned grade C 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.
Hidden instructionshighPrompt injection
Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.
<!-- Adapted from addyosmani/agent-skills (MIT © 2025 Addy Osmani). This is a STRUCTURAL REWRITE — upstream targets React/TypeScript/Tailwind UI. This skill retargets the same goals (production-quality, accessible, perfo How it starts
The opening of the file, as written. The whole thing — 618 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Frontend UI Engineering — Avalonia
Overview
Build production-quality Avalonia UIs that are accessible, performant, and visually polished. The goal is UI that looks like it was built by a design-aware .NET engineer at a top company — not like it was generated by an AI. That means real design-system adherence, proper keyboard navigation and screen-reader support, compiled XAML bindings for performance and type safety, thoughtful theming that respects light/dark/system variants, and no generic "AI aesthetic."
When to Use
- Building new Avalonia views or windows
- Modifying existing user-facing interfaces
- Implementing adaptive layouts for desktop + mobile + browser targets
- Adding interactivity or state management in view-models
- Fixing visual or UX issues (binding failures, theming bugs, focus traps)
- Migrating between Avalonia versions (11.x ↔ 12.x)
When NOT to use: backend-only changes in MyApp.Core / MyApp.Infrastructure, CLI tools, or code that doesn't render in an Avalonia view.
Related:
context-engineeringfor setting up CLAUDE.md +.editorconfigfor an Avalonia projectintegration-testing-dotnetfor testing views withAvalonia.Headless.XUnitperformance-optimization-dotnetfor virtualized lists, binding overhead, and startup-time tuning- The companion avalonia-dev plugin in this marketplace (
/avalonia-review) for structural reviews of existing Avalonia solutions — design token extraction, theming, project layout, phased migration
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 · 618 lines · 110 tokens per session scan C 253133543685
frontend-ui-engineering-avalonia is a skill published in the GitHub repository peterblazejewicz/claude-plugins (7 stars, last pushed 2mo ago), licensed MIT. It adds 110 tokens to every session and 7,294 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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