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 medy-gribkov/arcana --skill react-nativegit clone --depth 1 https://github.com/medy-gribkov/arcanaWrote 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/medy-gribkov/arcana/react-native)<a href="https://agentmods.dev/skills/medy-gribkov/arcana/react-native"><img src="https://agentmods.dev/badge/skills/medy-gribkov/arcana/react-native/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/medy-gribkov/arcana/react-native"><img src="https://agentmods.dev/badge/skills/medy-gribkov/arcana/react-native.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 | $0.00034 | $0.01381 |
| Opus 5.5 | $0.00014 | $0.00552 |
| Sonnet 5.5 | $0.00007 | $0.00276 |
| Haiku 4.5 | $0.00003 | $0.00138 |
Grade A, and why
react-native 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 — 226 lines — stays where its author put it; the contents beside it link to each section on GitHub.
React Native Mobile Development
Expert guidance for building production-ready React Native applications. Covers architecture decisions, performance optimization, navigation, state management, and native integration.
Project Setup and Workflow Selection
BAD: Starting with bare workflow without justification
npx react-native init MyApp
# Adds unnecessary native complexity from day one
# Requires Xcode/Android Studio setup immediately
GOOD: Start with Expo, eject only when needed
npx create-expo-app@latest MyApp --template blank-typescript
cd MyApp
# Expo provides:
# - Instant dev environment (no Xcode/Android Studio)
# - OTA updates via EAS
# - Prebuild for native customization
# - Standard libraries (camera, location, etc.)
# When you need custom native code:
npx expo prebuild
# Generates ios/ and android/ directories
# Maintains Expo libraries, adds native flexibility
When to use bare workflow:
- Heavy native module customization required
- Existing native iOS/Android codebase integration
- Libraries incompatible with Expo (rare in 2026)
Navigation Architecture
BAD: Navigation without type safety or deep linking
// No type checking on navigation params
function HomeScreen({ navigation }) {
return (
<Button
title="Go to Profile"
onPress={() => navigation.navigate('Profile', { userId: '123' })}
// Typo in route name causes runtime crash
/>
);
}
GOOD: React Navigation with TypeScript and deep linking
// types/navigation.ts
import { NavigationProp } from '@react-navigation/native';
export type RootStackParamList = {
Home: undefined;
Profile: { userId: string };
Settings: { section?: 'privacy' | 'notifications' };
};
export type AppNavigation = NavigationProp<RootStackParamList>;
// App.tsx
import { NavigationContainer } from '@react-navigation/native';
import { createNativeStackNavigator } from '@react-navigation/native-stack';
const Stack = createNativeStackNavigator<RootStackParamList>();
const linking = {
prefixes: ['myapp://', 'https://myapp.com'],
config: {
screens: {
Home: '',
Profile: 'user/:userId',
Settings: 'settings/:section?',
},
},
};
export default function App() {
return (
<NavigationContainer linking={linking}>
<Stack.Navigator>
<Stack.Screen name="Home" component={HomeScreen} />
<Stack.Screen name="Profile" component={ProfileScreen} />
<Stack.Screen name="Settings" component={SettingsScreen} />
</Stack.Navigator>
</NavigationContainer>
);
}
// HomeScreen.tsx
import { useNavigation } from '@react-navigation/native';
import type { AppNavigation } from './types/navigation';
function HomeScreen() {
const navigation = useNavigation<AppNavigation>();
return (
<Button
title="Go to Profile"
onPress={() => navigation.navigate('Profile', { userId: '123' })}
// TypeScript validates route name and params
/>
);
}
What ships with it
1 file 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.
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 · 226 lines · 34 tokens per session scan A afb3303872d8
react-native is a skill published in the GitHub repository medy-gribkov/arcana (1 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 34 tokens to every session and 1,381 once invoked, about $0.0001 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 2026-08-31.
Other skills, from other repositories
react-component
Build production-ready React components — hooks, context, accessibility, TypeScript types, and Storybook stories.
kotlin-patterns
Kotlin: coroutines, Flow, sealed/data classes, null safety, Ktor, Compose, KMP. Triggers: Kotlin, coroutine, Flow, suspend, Ktor, Jetpack Compose, KMP, kotlinx.
flutter-patterns
Flutter/Dart: widgets, state mgmt (Riverpod/Bloc), navigation, platform channels. Triggers: Flutter, Dart, widget, Riverpod, Bloc, pubspec, hot reload.
android-development
Android development with Kotlin, Jetpack Compose, and modern Android architecture. Use when building Android apps, implementing Material Design, or following Android best practices.
ios-development
Comprehensive guide for building native Apple platform applications.
agent-flutter-developer
Specialist subagent: Flutter/Dart cross-platform development, Riverpod state management, and platform channels specialist. Use when building Flutter apps, implementing state management, or working with native platform features. Trigger phrases: Flutter, Dart, Riverpod, Bloc, widget, MaterialApp, GoRouter, platform…