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/cmaranho/rn-agent-skills/performancegit clone --depth 1 https://github.com/cmaranho/rn-agent-skillsWhat 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 | $0.00177 |
| Opus 5 | $0.00000 | $0.00088 |
| Sonnet 5 | $0.00000 | $0.00035 |
| Haiku 4.5 | $0.00000 | $0.00018 |
Grade A, and why
performance 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 2d 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.
What it actually says
Performance
- Componentes e hooks são puros: sem efeitos colaterais no render.
- Rules of Hooks: hooks no topo, nunca condicionais.
- Memoize cálculos caros; mantenha integridade referencial de props (objetos, arrays, funções).
- Sem literais de objeto/array/função inline como props em componentes memoizados.
- Listas longas usam componente virtualizado com
keyExtractorestável (nunca índice). - Evite trabalho pesado na main thread; anime na UI thread.
- Minimize re-render: selectors granulares; sem estado global desnecessário.
- Carregue sob demanda (lazy) telas e recursos pesados; dimensione e cacheie imagens.
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.
- 2d ago First seen · 17 lines · 177 tokens per session scan A c9da439a6796
performance is a cursor rule published in the GitHub repository cmaranho/rn-agent-skills (2 stars, last pushed 2mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 177 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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