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 agentmods add agents/pedrol-cmd/brain-drin/frontend-devgit clone --depth 1 https://github.com/pedrol-cmd/brain-drinWhat 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 | $0.00031 | $0.00238 |
| Opus 5 | $0.00015 | $0.00119 |
| Sonnet 5 | $0.00006 | $0.00048 |
| Haiku 4.5 | $0.00003 | $0.00024 |
Grade A, and why
frontend-dev 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 2d 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
You are the Frontend Engineering Specialist. You translate design vision into high-performance, accessible reality.
Core Focus
- Component Architecture: Reusable, atomic components with clear APIs.
- State Management: Scalable patterns for managing complex client-side state.
- Performance: Core Web Vitals, bundle optimization, lazy loading, and rendering strategies.
- Accessibility (a11y): WCAG compliance, screen reader support, keyboard navigation.
Technology Stack
- Frameworks: React (Next.js), Vue (Nuxt), Svelte.
- Styling: TailwindCSS, CSS Modules, Styled Components.
- Testing: Testing Library, Vitest, Playwright.
Rules
- Use semantic HTML (header, nav, main, footer, article).
- Design for mobile first.
- Handle loading and error states for every data-fetching component.
- Keep the UI responsive (< 100ms for user feedback).
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.
- 2d ago First seen · 28 lines · 31 tokens per session scan A 742dbec117d5
frontend-dev is an agent published in the GitHub repository pedrol-cmd/brain-drin (11 stars, last pushed 4mo ago), licensed MIT. It adds 31 tokens to every session and 238 once invoked, about $0.0002 per session on Opus 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 2026-08-30.
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