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/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/react-specialist)<a href="https://agentmods.dev/agents/nickcrew/claude-cortex/react-specialist"><img src="https://agentmods.dev/badge/agents/nickcrew/claude-cortex/react-specialist/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/nickcrew/claude-cortex/react-specialist"><img src="https://agentmods.dev/badge/agents/nickcrew/claude-cortex/react-specialist.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 | $0.00038 | $0.00754 |
| Opus 5.5 | $0.00015 | $0.00302 |
| Sonnet 5.5 | $0.00008 | $0.00151 |
| Haiku 4.5 | $0.00004 | $0.00075 |
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 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- react-specialist — 89% identical, 19 lines differ
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.
- 1mo ago First seen · 104 lines · 38 tokens per session scan A ff4e650fb98d
react-specialist is an agent published in the GitHub repository NickCrew/Claude-Cortex (56 stars, last pushed 3mo ago), licensed MIT. It adds 38 tokens to every session and 754 once invoked, about $0.0002 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
senior-ux-ui-specialist
Usability and accessibility reviewer applying Nielsen heuristics, WCAG 2.1, keyboard/screen reader audits, and user flow analysis.
ux-strategist
Isolated batch agent for UX audit and strategy. Called by another workflow, or in parallel (e.g. "run heuristic, journey, and IA lenses at once"). Batch version of the ux-strategy skill — same methods (ux-methods.md), no gates or back-and-forth; takes a brief and returns one strategy/diagnosis report. Does not produce…
frontend-architect
Frontend architecture expert agent for UI/UX design, component structure, and Design System management. Handles React, Next.js, and modern frontend patterns. Use proactively when user needs UI architecture decisions, component design, Design System setup, or frontend code review. Triggers: frontend, UI architecture…
frontend-ui-component-agent
/ui-component-agent or @ui-component-agent.
frontend-specialist
A specialist coding agent for building user interfaces with React, Next.js, Vue, or Svelte. It also checks usability and accessibility, such as keyboard support, labels, and image descriptions.
animation-specialist
Animations, transitions, and gesture handling expert for shadcn/ui. Specializes in micro-interactions, page transitions, and smooth user experiences.