How to Fix AI Coding Agents Using Outdated Next.js APIs

AI agents trained on older Next.js data routinely produce getServerSideProps, getStaticProps, and next/router imports in App Router projects where none of those APIs exist.

The symptom

The agent scaffolds a page using Pages Router conventions inside an app/ directory, causing a build error or silent no-op.

// app/dashboard/page.tsx — WRONG
export async function getServerSideProps() {
  const data = await fetchData();
  return { props: { data } };
}

export default function Dashboard({ data }) {
  return <div>{data.title}</div>;
}

The getServerSideProps export is silently ignored in the App Router; the page renders with no data and no error.

Why it happens

Models are trained on massive Next.js corpora that skews heavily toward pre-13 Pages Router patterns. App Router was introduced in Next.js 13 (stable in 14) and the training cut-off for many models predates widespread adoption. The agent conflates the two paradigms because both live in files named page.tsx.

How to spot it

• Imports from "next/router" instead of "next/navigation" in an app/ directory.
• getServerSideProps, getStaticProps, or getStaticPaths exported from files under app/.
• useRouter called without "use client" at the top of the file.
• next.config.js still uses experimental.appDir (removed in Next.js 14).

How to fix it

Replace data-fetching exports with async Server Components and use the next/navigation hooks client-side.

// app/dashboard/page.tsx — CORRECT
async function fetchData() {
  const res = await fetch("https://api.example.com/data", {
    next: { revalidate: 60 },
  });
  return res.json();
}

export default async function Dashboard() {
  const data = await fetchData();
  return <div>{data.title}</div>;
}

Checklist:

[ ] No getServerSideProps / getStaticProps inside app/
[ ] Use "next/navigation" (useRouter, usePathname, useSearchParams) not "next/router"
[ ] Data fetching is async in the Server Component, not in a prop export
[ ] next.config.js uses next.config.mjs and removes experimental.appDir
[ ] Client-only hooks (useRouter etc.) are inside "use client" components

Fix Prompt

This file uses Pages Router APIs (getServerSideProps, getStaticProps,
next/router) inside an App Router project. Rewrite it using App Router
conventions: async Server Components for data fetching, next/navigation for
routing hooks, and "use client" only where browser APIs are required.
Do not add any Pages Router exports.

Test

# Fail fast: no Pages Router exports should appear under app/
grep -rn "getServerSideProps\|getStaticProps\|getStaticPaths" app/ && echo "FAIL: Pages Router API found" || echo "OK"

# Confirm correct navigation import
grep -rn "from \"next/router\"" app/ && echo "FAIL: use next/navigation instead" || echo "OK"