Borrowing it
Nothing to install: this file belongs to ahonn/dotfiles. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/ahonn/dotfiles/master/.claude/skills/react-best-practices/SKILL.mdgit clone --depth 1 https://github.com/ahonn/dotfilesWrote 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/skills/ahonn/dotfiles/react-best-practices)<a href="https://agentmods.dev/skills/ahonn/dotfiles/react-best-practices"><img src="https://agentmods.dev/badge/skills/ahonn/dotfiles/react-best-practices/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/skills/ahonn/dotfiles/react-best-practices"><img src="https://agentmods.dev/badge/skills/ahonn/dotfiles/react-best-practices.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00020 | $0.00713 |
| Opus 5.5 | $0.00008 | $0.00285 |
| Sonnet 5.5 | $0.00004 | $0.00143 |
| Haiku 4.5 | $0.00002 | $0.00071 |
Grade A, and why
react-best-practices 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 20d 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 — 42 lines — stays where its author put it; the contents beside it link to each section on GitHub.
React Performance and State Design
Start from the reported behavior and relevant implementation. Select only the references that address the task; the catalog is not a checklist to apply to every component.
Establish applicability
- Inspect the installed React version, framework, target platform, build configuration, and existing compiler setup before proposing version-dependent changes.
- Identify the bottleneck with a reproduction, profiler trace, bundle report, or concrete dependency path. If measurement is unavailable, label the diagnosis as a hypothesis and explain how to validate it.
- Prefer a focused change with an observable benefit. Do not add or remove memoization, introduce caching, change build tooling, or preload resources without a reason tied to the task.
- Follow the project's state, effect, and data-fetching conventions. Web rendering, SSR, and framework-specific examples do not automatically apply to React Native or a different framework.
Read by problem
| Problem or decision | Relevant references |
|---|---|
| Redundant state or synchronization bugs | State structure, immutable updates, effect pitfalls |
| A specific hook lifecycle or API question | Hooks guide |
| Requests wait on independent work | Waterfall elimination, parallel requests |
| Bundle report shows costly imports or initial code | Barrel imports, dynamic imports |
| Resource loading delays a likely user action | Preload on intent |
| Profiler shows costly repeated rendering | Memoization strategy, context splitting |
| Non-urgent rendering blocks an interaction | Transitions |
| Compiler adoption or compilation behavior is in scope | React Compiler |
| Repeated lookup cost is significant | Set and Map lookups |
| List identity or unexpected remounts | Key patterns |
| Expensive off-screen web content | Content visibility |
| Server-rendered web content visibly changes on hydration | Hydration flicker |
| Repeated static JSX creation is relevant to a measured cost | Hoist static JSX |
| Repeated server work or cache correctness | Server caching |
What ships with it
19 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/async-parallel-requests.md 3.3 KB
- references/async-waterfall-elimination.md 4.4 KB
- references/bundle-barrel-imports.md 3.2 KB
- references/bundle-dynamic-import.md 3.9 KB
- references/bundle-preload.md 2.9 KB
- references/effect-pitfalls.md 5.3 KB
- references/hooks-guide.md 4.3 KB
- references/immutable-updates.md 4.2 KB
- references/js-set-map-lookups.md 4.4 KB
- references/react-compiler.md 5.8 KB
- references/rendering-content-visibility.md 3.9 KB
- references/rendering-hoist-static-jsx.md 3.6 KB
- references/rendering-hydration-flicker.md 4.1 KB
- references/rendering-key-patterns.md 4.9 KB
- references/rerender-context-splitting.md 5.0 KB
- references/rerender-memo-strategy.md 5.6 KB
- references/rerender-transitions.md 4.4 KB
- references/server-cache-patterns.md 4.9 KB
- references/state-structure.md 4.9 KB
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.
- 20d ago Changed · -53 lines · -83 tokens per session 5d8860ef6e80
- 1mo ago First seen · 95 lines · 103 tokens per session scan A 9667b78b8abd
react-best-practices is a skill published in the GitHub repository ahonn/dotfiles (63 stars, last pushed 6d ago), licensed MIT. It adds 20 tokens to every session and 713 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 2026-09-03.
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