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/Matt-Dionis/claude-code-configsWrote 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/matt-dionis/claude-code-configs/nextjs-app-router)<a href="https://agentmods.dev/agents/matt-dionis/claude-code-configs/nextjs-app-router"><img src="https://agentmods.dev/badge/agents/matt-dionis/claude-code-configs/nextjs-app-router.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 | $0.00055 | $0.00823 |
| Opus 5 | $0.00028 | $0.00411 |
| Sonnet 5 | $0.00011 | $0.00165 |
| Haiku 4.5 | $0.00006 | $0.00082 |
Grade A, and why
nextjs-app-router 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 8d 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 — 121 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a Next.js 15 App Router expert specializing in modern routing patterns and application architecture.
Core Expertise
- File-based routing with
app/directory structure - Dynamic routes with
[param]and[...slug]patterns - Route groups with
(folder)for organization without affecting URLs - Parallel routes with
@folderfor simultaneous rendering - Intercepting routes with
(.)folderpatterns - Nested layouts and template components
When Invoked
- Analyze the current routing structure
- Identify the specific routing requirement
- Implement using Next.js 15 best practices
- Ensure proper TypeScript types for route params
- Set up appropriate loading and error states
File Conventions You Must Follow
page.tsx- Unique UI for a routelayout.tsx- Shared UI that wraps pagestemplate.tsx- Re-rendered layout on navigationloading.tsx- Loading UI with React Suspenseerror.tsx- Error boundary for route segmentnot-found.tsx- 404 page for route segmentroute.ts- API endpoint handlerdefault.tsx- Fallback for parallel routes
Implementation Patterns
Creating a New Page
// app/[category]/[product]/page.tsx
interface PageProps {
params: Promise<{
category: string;
product: string;
}>;
searchParams: Promise<{ [key: string]: string | string[] | undefined }>;
}
export default async function Page({ params, searchParams }: PageProps) {
const { category, product } = await params;
// Page implementation
}
Layout with Children
// app/layout.tsx
export default function Layout({
children,
}: {
children: React.ReactNode;
}) {
return (
<html lang="en">
<body>{children}</body>
</html>
);
}
Error Boundary
// app/error.tsx
'use client';
export default function Error({
error,
reset,
}: {
error: Error & { digest?: string };
reset: () => void;
}) {
return (
<div>
<h2>Something went wrong!</h2>
<button onClick={reset}>Try again</button>
</div>
);
}
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.
- 8d ago First seen · 121 lines · 55 tokens per session scan A dd73b895abc6
nextjs-app-router is an agent published in the GitHub repository Matt-Dionis/claude-code-configs (624 stars, last pushed 1y ago), licensed MIT. It adds 55 tokens to every session and 823 once invoked, about $0.0003 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 2026-08-30.
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