Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/VidyFoo/antigravity-skill-enginenpx agentmods add skills/vidyfoo/antigravity-skill-engine/fullstack-guideWrote 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/vidyfoo/antigravity-skill-engine/fullstack-guide)<a href="https://agentmods.dev/skills/vidyfoo/antigravity-skill-engine/fullstack-guide"><img src="https://agentmods.dev/badge/skills/vidyfoo/antigravity-skill-engine/fullstack-guide/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/vidyfoo/antigravity-skill-engine/fullstack-guide"><img src="https://agentmods.dev/badge/skills/vidyfoo/antigravity-skill-engine/fullstack-guide.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00074 | $0.01087 |
| Opus 5.5 | $0.00030 | $0.00435 |
| Sonnet 5.5 | $0.00015 | $0.00217 |
| Haiku 4.5 | $0.00007 | $0.00109 |
Grade A, and why
fullstack-guide 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.
How it starts
The opening of the file, as written. The whole thing — 186 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Frontend Development Guidelines
Purpose
Comprehensive guide for modern React development, emphasizing Suspense-based data fetching, lazy loading, proper file organization, and performance optimization.
When to Use This Skill
- Creating new components or pages
- Building new features
- Fetching data with TanStack Query
- Setting up routing with TanStack Router
- Styling components with MUI v7
- Performance optimization
- Organizing frontend code
- TypeScript best practices
Quick Start
New Component Checklist
Creating a component? Follow this checklist:
- Use
React.FC<Props>pattern with TypeScript - Lazy load if heavy component:
React.lazy(() => import()) - Wrap in
<SuspenseLoader>for loading states - Use
useSuspenseQueryfor data fetching - Import aliases (@/, ~types, ~components)
- Event handlers with
useCallback - No early returns for loading states
Core Patterns
Component Pattern
import React, { useState, useCallback } from 'react';
import { Box, Paper } from '@mui/material';
import { useSuspenseQuery } from '@tanstack/react-query';
import { featureApi } from '../api/featureApi';
import type { FeatureData } from '~types/feature';
interface MyComponentProps {
id: number;
onAction?: () => void;
}
export const MyComponent: React.FC<MyComponentProps> = ({ id, onAction }) => {
const [state, setState] = useState<string>('');
const { data } = useSuspenseQuery({
queryKey: ['feature', id],
queryFn: () => featureApi.getFeature(id),
});
const handleAction = useCallback(() => {
setState('updated');
onAction?.();
}, [onAction]);
return (
<Box sx={{ p: 2 }}>
<Paper sx={{ p: 3 }}>
{/* Content */}
</Paper>
</Box>
);
};
export default MyComponent;
Data Fetching
// Use useSuspenseQuery - No isLoading checks needed!
const { data } = useSuspenseQuery({
queryKey: ['myEntity', id],
queryFn: () => myFeatureApi.getEntity(id),
});
// data is ALWAYS defined (Suspense handles loading)
What ships with it
12 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.
- resources/common-patterns.md 4.8 KB
- resources/component-patterns.md 4.5 KB
- resources/data-fetching.md 5.4 KB
- resources/file-organization.md 4.9 KB
- resources/loading-and-error-states.md 5.5 KB
- resources/resources/architecture-overview.md 7.8 KB
- resources/resources/async-and-errors.md 6.1 KB
- resources/resources/testing-guide.md 6.9 KB
- resources/resources/validation-patterns.md 7.8 KB
- resources/routing-guide.md 4.7 KB
- resources/styling-guide.md 4.6 KB
- resources/typescript-standards.md 5.4 KB
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 · 186 lines · 74 tokens per session scan A b7394776dc53
fullstack-guide is a skill published in the GitHub repository VidyFoo/antigravity-skill-engine (12 stars, last pushed 1mo ago), licensed MIT. It adds 74 tokens to every session and 1,087 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 2026-08-30.
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