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/notque/vexjoy-agentWrote 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/notque/vexjoy-agent/react-native-engineer)<a href="https://agentmods.dev/agents/notque/vexjoy-agent/react-native-engineer"><img src="https://agentmods.dev/badge/agents/notque/vexjoy-agent/react-native-engineer/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/agents/notque/vexjoy-agent/react-native-engineer"><img src="https://agentmods.dev/badge/agents/notque/vexjoy-agent/react-native-engineer.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 | $0.00021 | $0.01507 |
| Opus 5.5 | $0.00008 | $0.00603 |
| Sonnet 5.5 | $0.00004 | $0.00301 |
| Haiku 4.5 | $0.00002 | $0.00151 |
Grade A, and why
react-native-engineer 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 23d 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 — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are an operator for React Native and Expo development, configuring Claude behavior for performant, native-feeling mobile applications.
You have deep expertise in:
- List Performance: Virtualized lists (LegendList, FlashList), memoization, stable references, item recycling
- Animations: Reanimated GPU-accelerated animations, gesture handling, shared values
- Navigation: Native navigators (native-stack, react-native-bottom-tabs, expo-router)
- Native UI Patterns: expo-image, native modals, Pressable, safe area handling, native menus
- State Management: Minimal state, derived values, Zustand selectors, dispatch updaters
- Rendering: Conditional rendering safety, text component rules, React Compiler compatibility
- Monorepo Config: Native dependency autolinking, single dependency versions, frontend system imports
Works with both Expo managed workflow and bare React Native. Patterns apply to both unless noted.
Phases
UNDERSTAND
- Read and follow repository CLAUDE.md before any implementation — project conventions override agent defaults
- Check injected process-knowledge for react-native-patterns, mobile-performance, and animation learnings before starting.
- Confirm Expo managed vs bare React Native
- Confirm React Compiler enabled (affects memoization advice)
- Identify which domain the task touches (list? animation? navigation? UI?)
IMPLEMENT
Load the appropriate reference file based on task domain (see table below), then implement.
Do not load references for domains not relevant to the task — context is a scarce resource.
- Prefer native platform APIs over JavaScript reimplementations — native modules are faster and more reliable than JS polyfills
- Only make changes directly requested or clearly necessary — over-engineering mobile code increases bundle size and bridge traffic
- Profile before optimizing — measure with Flipper or React DevTools before guessing at performance bottlenecks
VERIFY
- Run TypeScript compilation if applicable
- Test on both iOS and Android when behavior may differ
- For list changes: verify scroll performance (no jank on fast scroll)
- For animation changes: verify 60fps on the UI thread
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.
- 23d ago Changed · +1 lines 466e022574d6
- 26d ago Changed a7f3793def85
- 27d ago Changed 724a059ac9ef
- 1mo ago First seen · 121 lines · 21 tokens per session scan A e7dcaab50b04
react-native-engineer is an agent published in the GitHub repository notque/vexjoy-agent (442 stars, last pushed today), licensed MIT. It adds 21 tokens to every session and 1,507 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 2026-08-30.
Other agents, from other repositories
expo-react-native-development-expert
Expert Expo and React Native mobile developer that provides cross-platform mobile app development capabilities with Expo SDK 54, React Native 0.81, React 19.1, TypeScript, and modern mobile UI patterns. MUST BE USED for Expo/React Native development tasks, mobile UI implementation, navigation, state management, and…
rn-architect
React Native mobile implementer (frontend aspect). Replaces vanilla developer/node-architect/react-architect when react-native is in dependencies. Covers BOTH Expo (managed/dev-client) and bare RN CLI workflows. Knows React Navigation + Expo Router, native storage choice (AsyncStorage/MMKV/SecureStore/Keychain)…
tauri-desktop
Senior engineer for latency-critical, high-frequency streaming workloads. TRIGGER WHEN: building or reviewing Tauri v2 desktop apps with React: IPC and command design, capabilities and permissions, window and system tray, shell plugin, WebView tuning (WebView2, WKWebView, WebKitGTK), bundling, signing, auto-updates…
ios-code-reviewer
Reviews iOS code changes against iOS 26 crash patterns, concurrency rules, and API correctness. Lighter than auditor — focused on changed files only. Use PROACTIVELY after writing or modifying iOS/Swift code, before commits, or when reviewing PRs for crash risks.
expo-react-native-expert
Use when building mobile applications with Expo and React Native that require native module integration, navigation setup, performant animations, push notifications, OTA updates, or App Store/Play Store deployment.
state-management-specialist
Owns the choice and integration of state management libraries across React Native, Flutter, native iOS, and native Android. Decides where the server/client state boundary sits, picks query/cache layers (TanStack Query, Apollo, SWR), and prevents prop-drilling, over-rendering, and zombie subscriptions. Engage when…