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.
git clone --depth 1 https://github.com/Consensys/ask-o11y-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/rules/consensys/ask-o11y-plugin/frontend-patterns)<a href="https://agentmods.dev/rules/consensys/ask-o11y-plugin/frontend-patterns"><img src="https://agentmods.dev/badge/rules/consensys/ask-o11y-plugin/frontend-patterns/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/rules/consensys/ask-o11y-plugin/frontend-patterns"><img src="https://agentmods.dev/badge/rules/consensys/ask-o11y-plugin/frontend-patterns.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 | $0.00000 | $0.00374 |
| Opus 5.5 | $0.00000 | $0.00150 |
| Sonnet 5.5 | $0.00000 | $0.00075 |
| Haiku 4.5 | $0.00000 | $0.00037 |
Grade A, and why
frontend-patterns 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.
What it actually says
Frontend Patterns
Reference: CLAUDE.md is the authoritative source.
Theme Integration — NEVER hardcode colors
// ✅ CORRECT — semantic Tailwind classes
<div className="bg-background text-primary border-weak">
<span className="text-error">Error occurred</span>
// ❌ WRONG — hardcoded colors break dark/light mode
<div className="bg-gray-900 text-white border-gray-700">
Semantic classes:
- Backgrounds:
bg-backgroundbg-secondarybg-surfacebg-canvasbg-elevated - Text:
text-primarytext-secondarytext-disabledtext-link - Borders:
border-weakborder-mediumborder-strong - Status:
text-successtext-warningtext-errortext-info
Prefer @grafana/ui components over custom implementations.
Error Handling — No silent failures, no console.*
// ✅ CORRECT — surface errors in the UI
} catch (err) {
setError('Failed to load tools. Please try again.');
}
// ❌ WRONG — swallowed error, console pollution
} catch (err) {
console.error(err);
}
No console.log, console.error, or console.warn in shipped code.
Component Patterns
- Functional components with hooks only — no class components
async/awaitnot.then()/.catch()- Custom hooks for reusable business logic (
useChat,useSessionManager) useMemo/useCallbackfor performance-sensitive computations
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 · 51 lines · 0 tokens per session scan A bef2e2128ece
frontend-patterns is a cursor rule published in the GitHub repository Consensys/ask-o11y-plugin (42 stars, last pushed 22d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 374 tokens. 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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