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/beel-collab/presets.devWrote 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/rules/beel-collab/presets.dev/react-rules)<a href="https://agentmods.dev/rules/beel-collab/presets.dev/react-rules"><img src="https://agentmods.dev/badge/rules/beel-collab/presets.dev/react-rules/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/rules/beel-collab/presets.dev/react-rules"><img src="https://agentmods.dev/badge/rules/beel-collab/presets.dev/react-rules.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 | $0.00000 | $0.01298 |
| Opus 5.5 | $0.00000 | $0.00519 |
| Sonnet 5.5 | $0.00000 | $0.00260 |
| Haiku 4.5 | $0.00000 | $0.00130 |
Grade A, and why
react-rules 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.
How it starts
The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.
React Rules for Cursor: Components, State and Effects
Install
Install the native export at .cursor/rules/react-rules.mdc.
Copy that export, not this catalog file. Catalog fields such as tools and author are for presets.dev.
Install one skill file per name. Cursor, GitHub Copilot, Codex, Antigravity CLI, and Devin can all read .agents/skills, so a second copy with the same name collides.
React Rules for Cursor: Components, State and Effects
File-scoped Cursor rule for React. It attaches when a matching file is in context.
Updated for React 19.3.1, Nov 2026
Do not upgrade dependencies or the framework version unless the task asks.
Project shape
Build the tree from function components. One component owns one job. Put shared UI in the folder the project already uses. Colocate a component's test next to it when that is the local pattern.
Props are the input. State is what this component owns. Derived values are computed while rendering. A parent owns state that two children must share.
State and rendering
Set state in response to an event or a completed request. Compute fullName from first and last during render. An effect that copies props into state goes stale and renders twice.
Use a functional update when the next state depends on the previous one. Include every reactive value a hook callback reads, or restructure so the callback does not close over a changing value.
Lists need a stable id as key. Index keys break when the list is reordered, filtered, or inserted into.
Effects
Effects synchronize with an external system: a subscription, a timer, a widget outside React. Return a cleanup that cancels the subscription or the timer. Do not fetch in an effect when the framework already loads data in a server component or a router loader. If the project does fetch in effects, abort on cleanup and ignore a response that arrives after unmount.
Strict Mode runs setup and cleanup an extra time in development. A cleanup that is missing will show up there. Do not "fix" that by disabling Strict Mode.
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 · 120 lines · 0 tokens per session scan A 459f4e015c28
react-rules is a cursor rule published in the GitHub repository beel-collab/presets.dev (3 stars, last pushed yesterday), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,298 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 2026-11-13.
react-rules compared with cursor rules from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| react-rulesbeel-collab/presets.dev | Cursor rule | 3 | yesterday | MIT | A | 0 | Cursor |
| ponytailDietrichGebert/ponytail | Cursor rule | 190k | 15d ago | MIT | A | 604 | Cursor |
| angular-20angular/angular | Cursor rule | 101k | today | MIT | A | 0 | Cursor |
| dev-standardapache/superset | Cursor rule | 76k | today | Apache-2.0 | A | 1,147 | Cursor |
| prefer-direct-imports-over-module-mocksprisma/orm | Cursor rule | 48k | today | Apache-2.0 | A | 0 | Cursor |
| config-validation-and-normalizationprisma/orm | Cursor rule | 48k | today | Apache-2.0 | A | 0 | Cursor |
| control-plane-descriptorsprisma/orm | Cursor rule | 48k | today | Apache-2.0 | A | 0 | Cursor |