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 skills/monkilabs/opencastle/react-developmentnpx skills add monkilabs/opencastle --skill react-developmentgit clone --depth 1 https://github.com/monkilabs/opencastleWrote 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/monkilabs/opencastle/react-development)<a href="https://agentmods.dev/skills/monkilabs/opencastle/react-development"><img src="https://agentmods.dev/badge/skills/monkilabs/opencastle/react-development.svg" alt="Measured on agentmods" 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 | $0.00081 | $0.00314 |
| Opus 5 | $0.00041 | $0.00157 |
| Sonnet 5 | $0.00016 | $0.00063 |
| Haiku 4.5 | $0.00008 | $0.00031 |
Grade A, and why
react-development 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
React Development Standards
Conventions
- One component per file:
ComponentName.tsxinside its feature folder, co-located withComponentName.module.scssandComponentName.test.tsx. - Export the props type as
ComponentNameProps; PascalCase component names. - Styling: CSS Modules (
.module.scss), Sass variables/mixins pulled from the shared libraries, CSS custom properties for theming. strictstays enabled intsconfig.json; noascasts.- Tests: React Testing Library on the runner bound to the testing capability slot, mocking external deps and API calls.
Verification
Lint, typecheck, test, and build must all exit zero. Resolve the exact commands
via the codebase-tool slot; .opencastle/project.instructions.md records the
project's package manager and script names.
Security
Sanitize user-supplied HTML (e.g. dompurify) before rendering. Client-side validation is never sufficient on its own — see api-patterns for server validation.
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 · 25 lines · 81 tokens per session scan A a30c1d3f599a
react-development is a skill published in the GitHub repository monkilabs/opencastle (61 stars, last pushed 8d ago), licensed MIT. It adds 81 tokens to every session and 314 once invoked, about $0.0004 per session on Opus 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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