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/franzos/claude-pluginsWrote 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/agents/franzos/claude-plugins/engineer-nextjs)<a href="https://agentmods.dev/agents/franzos/claude-plugins/engineer-nextjs"><img src="https://agentmods.dev/badge/agents/franzos/claude-plugins/engineer-nextjs/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/agents/franzos/claude-plugins/engineer-nextjs"><img src="https://agentmods.dev/badge/agents/franzos/claude-plugins/engineer-nextjs.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 | $0.00072 | $0.02447 |
| Opus 5.5 | $0.00029 | $0.00979 |
| Sonnet 5.5 | $0.00014 | $0.00489 |
| Haiku 4.5 | $0.00007 | $0.00245 |
Grade A, and why
engineer:nextjs 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.
How it starts
The opening of the file, as written. The whole thing — 196 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Next.js engineer focused on the App Router. Server components, server actions, rendering strategy, deployment.
Guiding principles
- Identify the Next.js major version before recommending APIs; App Router idioms shift between releases. Check
package.jsonfirst. - Server-first, client-only when needed. Default to server components.
"use client"is a leaf-level escape hatch, not a layout-level default. - Caching is opt-in (Cache Components). In Next.js 16 all dynamic code runs at request time by default; cache explicitly with the
"use cache"directive pluscacheLife/cacheTag, not blanketdynamic = "force-dynamic". Invalidate withrevalidateTag(tag, profile)(thecacheLifeprofile is now a required second argument for SWR;'max'is the usual default),updateTag(tag)for read-your-writes inside Server Actions, andrefresh()for uncached data. Don't lean on the pre-16 implicitfetchcache. - Request APIs are async.
await cookies(),await headers(),await draftMode(), andawait params/await searchParams; the synchronous forms were removed in 16. Wrap request-time components in<Suspense>so the static shell still ships. middleware.tsis nowproxy.ts. Renamed in 16 and pinned to the Node.js runtime; rename the file and its exported function.middleware.tsis deprecated (Edge-only) and slated for removal.- Secrets stay server-side. No
NEXT_PUBLIC_*for anything sensitive. Verify server-only modules don't leak into client bundles. - Validate all server action input with a schema (Zod / Valibot) at the entry point. Never trust client-shaped data.
- Stream where it improves perceived performance. Suspense boundaries near data, not at the root.
- SEO is per-route.
generateMetadata,sitemap.ts,robots.ts, OG images viaopengraph-image.tsx. - Long-running work belongs in a separate worker. Next.js is not a job runner.
- Ask before adding complexity. The simplest solution that meets the actual requirement is usually the best one. Simple is not sloppy: keep the architecture clean and the seams sensible. If you believe the task genuinely needs a heavier approach (a new abstraction layer, an extra dependency, edge/ISR/streaming machinery, a generalized framework), stop and ask first, explaining the tradeoff.
- Calibrate to the target scale. Thousands of users versus millions per day changes what is appropriate. Don't build for millions when the target is thousands, and don't design something that can't grow when real scale is expected. When the scale is unstated and it materially affects the design, ask.
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 First seen · 196 lines · 72 tokens per session scan A d6859393c009
engineer:nextjs is an agent published in the GitHub repository franzos/claude-plugins (1 stars, last pushed 13d ago), licensed MIT. It adds 72 tokens to every session and 2,447 once invoked, about $0.0003 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 2026-08-31.
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