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 skills add jxoesneon/Ciel --skill nextjs-developmentgit clone --depth 1 https://github.com/jxoesneon/CielWrote 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/jxoesneon/ciel/nextjs-development)<a href="https://agentmods.dev/skills/jxoesneon/ciel/nextjs-development"><img src="https://agentmods.dev/badge/skills/jxoesneon/ciel/nextjs-development/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/jxoesneon/ciel/nextjs-development"><img src="https://agentmods.dev/badge/skills/jxoesneon/ciel/nextjs-development.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 | $0.00023 | $0.00422 |
| Opus 5.5 | $0.00009 | $0.00169 |
| Sonnet 5.5 | $0.00005 | $0.00084 |
| Haiku 4.5 | $0.00002 | $0.00042 |
Grade A, and why
nextjs-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 1mo 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
CIEL ADAPTATION: Next.js Development (The React Meta-Layer)
This skill formalizes the development of modern React applications using Next.js 16+. it prioritizes Turbopack for development and Server Components for production.
The Turbopack Workflow
- Dev Mode: Default to
next dev. Verify file-system caching is active in.next/. - HMR Integrity: If hot updates are slow, audit for massive barrel-imports or un-optimized third-party packages.
- Bundle Analysis: Use the experimental
bundleAnalyzerto find and tree-shake heavy dependencies.
Architecture Mandates
- Server Components (RSC): Default to Server Components. Use
"use client"ONLY for interactivity (events, state, hooks). - Data Fetching: Fetch data in Server Components via
fetch()with appropriaterevalidatetags. - Optimized I/O: Use
next/imagefor LCP images andnext/fontfor zero-CLS typography.
Performance Gates
- LCP: Target < 2.5s via server-side fetching and image priority.
- CLS: Target < 0.1 via fixed-ratio image containers and font-optimization.
- Cold Start: Audit middleware and global layouts for blocking I/O that slows down TTFB.
Anti-Patterns
- Prop Drilling RLS: Passing security context deep into Client Components instead of checking in RSC.
- Barrel Import Bloat: Importing 1 component from a 50-component index file (breaks tree-shaking).
- Global State Overkill: Using Redux/Zustand for data that can be managed by RSC and URL params.
What ships with it
1 file 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.
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.
- 1mo ago Changed · -13 lines a8741eb9427e
- 1mo ago First seen · 50 lines · 23 tokens per session scan A 5048445d262a
nextjs-development is a skill published in the GitHub repository jxoesneon/Ciel (1 stars, last pushed 4d ago), licensed Apache-2.0. It adds 23 tokens to every session and 422 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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