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 rules/ssakone/crossrule/reactgit clone --depth 1 https://github.com/ssakone/crossruleWhat 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 | $0.00000 | $0.00238 |
| Opus 5 | $0.00000 | $0.00119 |
| Sonnet 5 | $0.00000 | $0.00048 |
| Haiku 4.5 | $0.00000 | $0.00024 |
Grade A, and why
react 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 yesterday.
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
React Component Standards
Component Architecture
- Use functional components with React hooks for all new components
- Implement proper TypeScript interfaces for all component props
- Use React.memo for performance optimization when components have expensive renders
- Prefer composition over inheritance for component reusability
State Management
- Use useState for local component state
- Use useReducer for complex state logic with multiple sub-values
- Implement custom hooks to encapsulate and reuse stateful logic
- Avoid prop drilling; use Context API for deeply nested state sharing
Error Handling
- Implement Error Boundaries for graceful error handling in component trees
- Handle loading, error, and empty states appropriately in data-fetching components
- Use React Suspense for code splitting and lazy loading
- Provide meaningful error messages and fallback UI for users
Performance Best Practices
- Use useCallback and useMemo hooks to prevent unnecessary re-renders
- Implement lazy loading for route components and heavy dependencies
- Optimize bundle size by importing only needed modules from libraries
- Profile component performance regularly with React Developer Tools
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.
- yesterday First seen · 30 lines · 0 tokens per session scan A 607dbdac134e
react is a cursor rule published in the GitHub repository ssakone/crossrule (4 stars, last pushed 11mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 238 tokens. 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.
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