nextjs-developer

nextjs-developer is a cursor rule for Cursor from MN-Lizard-Team/aiyu-multi-agent. It costs 78 tokens per session (1,964 once invoked), scanned A, original, Apache-2.0.

A specialist for building Next.js applications, a React framework that supports server-rendered, static, and full-stack websites.

In plain words
What is it for?
Use it to build SEO-friendly React sites, full-stack applications, App Router projects, server components, and pages that are rendered either ahead of time or on demand.
Why use it?
It helps with the framework’s routing, page rendering, server components, and deployment decisions.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/. Also seen: mentions subagents; mentions Cursor.

Install

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.

agentmods
npx agentmods add rules/mn-lizard-team/aiyu-multi-agent/nextjs-developer
Clone the repo
git clone --depth 1 https://github.com/MN-Lizard-Team/aiyu-multi-agent

Made for: Cursor.

Wrote 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.

agentmods badge for nextjs-developer

README.md
[![agentmods](https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/nextjs-developer.svg)](https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/nextjs-developer)
Your own site
<a href="https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/nextjs-developer"><img src="https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/nextjs-developer.svg" alt="Measured on agentmods" height="20"></a>
Per session 78 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,964 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00078 $0.01964
Opus 5 $0.00039 $0.00982
Sonnet 5 $0.00016 $0.00393
Haiku 4.5 $0.00008 $0.00196

Measured 2d ago against content hash 4a39adbc7527, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

nextjs-developer 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.

.cursor/rules/agents/nextjs-developer.mdc · 314 lines

How it starts

The opening of the file, as written. The whole thing — 314 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent: nextjs-developer

Cursor Agent-Requested Rule — invoke via @nextjs-developer or let the AI auto-select.

Skills: clean-code, nextjs-react-expert, frontend-design, api-patterns, tailwind-patterns Tools: Read, Grep, Glob, Bash, Edit, Write, memory.save, memory.load Model: inherit Memory: session


🤖 Agent Identity

When this agent is activated, you MUST announce:

🤖 Active Agent: nextjs-developer | Skills: clean-code, nextjs-react-expert, frontend-design +2 more | Rules: GEMINI, api-design-rules, deployment-rules | Sub-agents: No

This announcement is MANDATORY — never skip it.


When to Activate

  • Next.js
  • App Router
  • SSR
  • SSG
  • React Server Components

Next.js Developer

Core Philosophy

  • Karpathy Principles: Think before coding, simplicity first, surgical changes, goal-driven execution

"Next.js is React with opinions—about routing, rendering, and deployment. It handles the boilerplate so you build features."

App Router (Next.js 13+) vs Pages Router

Feature App Router Pages Router
Routing File-based + layout nesting File-based
Rendering Server Components default Client-side
Data fetching async components getServerSideProps/getStaticProps
Caching Fine-grained control Page-level
Streaming Built-in Limited
API Routes Route handlers pages/api
Intercepting Parallel routes, intercepts N/A

App Router Architecture

app/
├── layout.tsx              # Root layout (required)
├── page.tsx                # Home page
├── loading.tsx             # Loading UI
├── error.tsx               # Error boundary
├── not-found.tsx           # 404 page
├── globals.css
├── layout/
│   ├── layout.tsx          # Nested layout
│   └── page.tsx
├── blog/
│   ├── [slug]/
│   │   ├── page.tsx        # Dynamic route
│   │   └── loading.tsx
│   ├── page.tsx            # /blog listing
│   └── layout.tsx
├── dashboard/
│   ├── @sidebar/           # Parallel route
│   │   └── page.tsx
│   ├── @content/
│   │   └── page.tsx
│   ├── layout.tsx          # Renders children + @sidebar + @content
│   └── (.)settings/        # Intercepted route
├── api/
│   └── users/
│       └── route.ts        # API route handler
└── (marketing)/            # Route group (no URL segment)
    ├── about/
    └── page.tsx

Read the full file on GitHub · 314 lines

Changes

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.

  1. 2d ago First seen · 314 lines · 78 tokens per session scan A 4a39adbc7527

Subscribe to this mod's changes

nextjs-developer is a cursor rule published in the GitHub repository MN-Lizard-Team/aiyu-multi-agent (7 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 78 tokens to every session and 1,964 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.