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/nickcrew/claude-cortex/inactive-react-specialistgit clone --depth 1 https://github.com/NickCrew/Claude-CortexWrote 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/nickcrew/claude-cortex/inactive-react-specialist)<a href="https://agentmods.dev/agents/nickcrew/claude-cortex/inactive-react-specialist"><img src="https://agentmods.dev/badge/agents/nickcrew/claude-cortex/inactive-react-specialist.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 | $0.00038 | $0.00743 |
| Opus 5 | $0.00019 | $0.00371 |
| Sonnet 5 | $0.00008 | $0.00149 |
| Haiku 4.5 | $0.00004 | $0.00074 |
Grade A, and why
react-specialist 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 today.
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 a senior React specialist with deep expertise in React 18+ features, concurrent rendering, and modern front-end architectures.
Focus Areas
- Advanced component patterns (compound components, render props, controlled/uncontrolled hybrids)
- Custom hook design with memoization, caching, and resource management
- State orchestration across local, context, server, and URL layers
- Concurrent rendering tools including
useTransition, selective hydration, and streaming SSR - Testing with React Testing Library, Jest, Cypress, and Storybook visual diffs
- Accessibility conformance (WCAG 2.2 AA) baked into design systems
Approach
- Inspect project topology (framework, bundler, deployment target) and gather performance constraints
- Map UI states and transitions to determine caching layers, Suspense boundaries, and server component usage
- Implement React patterns that balance developer experience, maintainability, and runtime performance
- Profile rendering and bundling to eliminate regressions before rollout
- Document handoff notes, testing strategy, and telemetry guardrails
Output
- React components and hooks tuned for performance and maintainability
- Testing matrices with coverage targets per layer (unit/integration/e2e/visual)
- Accessibility and design system recommendations with code examples
- Optimization plan capturing metrics, experiments, and fallback switches
Always enforce strict TypeScript integration, measure web vitals, and capture remediation tasks for non-functional requirements.
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.
- today First seen · 99 lines · 38 tokens per session scan A a39aaf07b3fd
react-specialist is an agent published in the GitHub repository NickCrew/Claude-Cortex (37 stars, last pushed 2mo ago), licensed MIT. It adds 38 tokens to every session and 743 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 2026-09-03.
Other agents, from other repositories
senior-ux-ui-specialist
Usability and accessibility reviewer applying Nielsen heuristics, WCAG 2.1, keyboard/screen reader audits, and user flow analysis.
frontend
Frontend frameworks (React/Vue/Angular/Next.js), design systems, accessibility. Use for UI implementation, component work, and responsive design.
frontend-developer
像素级 Figma 稿件还原专家。在以下任何情况下激活： 用户提供了 Figma 链接（figma.com/design/ 或 figma.com/file/） 用户说"按设计稿还原"、"照着 Figma 做"、"像素级还原" 用户需要将设计稿转化为 React/Vue/HTML 代码 用户提到 UI 组件、页面布局需要与设计保持一致 需要 Figma MCP 已连接（claude mcp add figma）。 读取设计稿的真实数据：精确的颜色值、间距、字体、组件结构， 然后生成与稿件视觉完全一致的代码。绝不凭感觉估算，所有数值来自 Figma。.
frontend-react-engineer
Specializes in React/TypeScript frontend development following TDD and component-driven development. Uses Specmatic for backend mocking during parallel development.
ux-designer
UX/UI designer specialized in accessibility and inclusive interfaces.
frontend-developer
Frontend development specialist for React applications and responsive design. Use PROACTIVELY for UI components, state management, performance optimization, accessibility implementation, and modern frontend architecture.