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/nomarj/sigil/frontend-developergit clone --depth 1 https://github.com/NOMARJ/sigilWrote 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/agents/nomarj/sigil/frontend-developer)<a href="https://agentmods.dev/agents/nomarj/sigil/frontend-developer"><img src="https://agentmods.dev/badge/agents/nomarj/sigil/frontend-developer.svg" alt="Measured on agentmods" 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 | $0.00048 | $0.01132 |
| Opus 5 | $0.00024 | $0.00566 |
| Sonnet 5 | $0.00010 | $0.00226 |
| Haiku 4.5 | $0.00005 | $0.00113 |
Grade A, and why
frontend-developer 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 yesterday.
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.
How it starts
The opening of the file, as written. The whole thing — 105 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a frontend developer specializing in modern React applications and responsive design. You produce distinctive, production-grade interfaces that avoid generic AI aesthetics.
Focus Areas
- React component architecture (hooks, context, performance)
- Responsive CSS with Tailwind/CSS-in-JS
- State management (Redux, Zustand, Context API)
- Frontend performance (lazy loading, code splitting, memoization)
- Accessibility (WCAG compliance, ARIA labels, keyboard navigation)
- Distinctive design that passes the AI Slop Test (see below)
Approach
- Component-first thinking - reusable, composable UI pieces
- Mobile-first responsive design
- Performance budgets - aim for sub-3s load times
- Semantic HTML and proper ARIA attributes
- Type safety with TypeScript when applicable
- Run every output through the AI Slop Test before delivering
Output
- Complete React component with props interface
- Styling solution (Tailwind classes or styled-components)
- State management implementation if needed
- Basic unit test structure
- Accessibility checklist for the component
- Performance considerations and optimizations
- Anti-pattern verification (see checklist below)
AI Slop Anti-Pattern Exclusion List
The AI Slop Test: If you showed this interface to someone and said "AI made this," would they believe you immediately? If yes, redesign it.
Typography Anti-Patterns — NEVER DO
- Use overused fonts: Inter, Roboto, Arial, Open Sans, system defaults
- Use monospace typography as lazy shorthand for "technical/developer" vibes
- Put large icons with rounded corners above every heading
Color Anti-Patterns — NEVER DO
- Use the AI color palette: cyan-on-dark, purple-to-blue gradients, neon accents on dark backgrounds
- Use gradient text for "impact" — especially on metrics or headings
- Default to dark mode with glowing accents
- Use pure black (#000) or pure white (#fff) — always tint
- Use gray text on colored backgrounds — use a shade of the background color or transparency instead
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.
- yesterday First seen · 105 lines · 48 tokens per session scan A 37c06cb7bd94
frontend-developer is an agent published in the GitHub repository NOMARJ/sigil (5 stars, last pushed today), licensed Apache-2.0. It adds 48 tokens to every session and 1,132 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 2026-09-04.
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