How I Made My Next.js Blog Serve Markdown Files for Agent Experience SEO (AX-SEO)

I’ll show you how to serve raw Markdown files in a Next.js blog using middleware and API routes, enabling Agent Experience SEO (AX-SEO).

AX-SEO focuses on optimizing content for AI agents, LLM-powered search engines, and automated crawlers that now play a major role in content discovery.

By the end of this post, you’ll be able to:

✅ Implement Next.js middleware for .md URL rewriting.
✅ Set up API routes to fetch and serve Markdown content.
✅ Optimize your blog for Agent Experience SEO (AI-driven search).
✅ Provide clean, structured data for AI-powered search engines.

Traditional SEO is no longer enough. AI search engines, LLM-powered assistants (ChatGPT, Perplexity, Google’s AI Overviews, etc.), and autonomous agents are now indexing and ranking content differently.

Why does AX-SEO matter?

• AI agents prefer structured content – Raw Markdown is easier to parse than HTML.

• LLMs use Markdown for training & retrieval – AI search engines extract structured text more efficiently.

• AX-SEO improves discoverability – AI-driven platforms rank content based on how well agents can process it.

If you want your blog optimized for AI-driven search, this guide is for you!

Most blogs serve only HTML, making extracting structured information hard for AI tools. Common mistakes include:

❌ Not offering raw text formats – AI agents struggle with unnecessary markup.
❌ Ignoring structured data for LLMs – AI search engines prioritize clean content.

This guide avoids these mistakes and ensures a future-proof content strategy for AI indexing.

How I Did It

Step 1: Middleware for .md Routing

I used Next.js Middleware to detect .md URLs and redirect them to an API route:

import type { NextRequest } from "next/server";
import { NextResponse } from "next/server";

export function middleware(req: NextRequest) {
  const url = req.nextUrl.clone();

  if (url.pathname.endsWith(".md")) {
    url.pathname = `/api${url.pathname}`;
    return NextResponse.rewrite(url);
  }

  return NextResponse.next();
}

export const config = {
  matcher: ["/blog/:path*.md", "/projects/:path*.md"],
};

Step 2: API Route to Serve Markdown

Next, I created API endpoints to fetch Markdown content:

import { readMarkdown } from "@/server/read-markdown-file";
import { NextRequest } from "next/server";

export async function GET(_req: NextRequest, { params: { slug } }: { params: { slug: string } }) {
  return readMarkdown(slug);
}

Step 3: Fetching Markdown Content from CMS

The readMarkdown the function retrieves the raw Markdown content:

import useBlogSlug from "@/features/posts/hooks/useBlogSlug";
import { NextResponse } from "next/server";

export async function readMarkdown(slug: string) {
  try {
    const {
      post: {
        content: { markdown },
      },
    } = await useBlogSlug({ params: { slug: slug.replace(".md", "") } });

    return new NextResponse(markdown, {
      headers: {
        "Content-Type": "text/plain",
      },
    });
  } catch (error) {
    console.error("Error reading markdown file:", error);
    return new NextResponse(JSON.stringify({ message: "Markdown file not found" }), { status: 404 });
  }
}

Step 4: Adding a Markdown Link to the Blog

To make the Markdown file accessible, I added a link on each blog page:

<Link href={`/api/${params.type}/${params.slug}.md`} passHref>
  View Markdown
</Link>

Now, every post has a “View Markdown” button that links to the raw .md version.

How This Boosts Agent Experience SEO (AX-SEO)

• ✅ AI-Optimized Content – Markdown is easier for AI bots to read than HTML.

• ✅ AX-SEO Ready – AI-powered search engines prefer structured text for ranking and retrieval.

• ✅ Faster AI Crawling – Lightweight Markdown improves indexing speed.

• ✅ Better Content Extraction – LLMs can fetch raw text for RAG-based applications.

• ✅ Scalable & Future-Proof – Works for blogs, docs, and AI knowledge bases.

Final Thoughts

With this approach, I made my Next.js blog serve Markdown dynamically, benefiting both humans and AI bots.

📂 Source Code: GitHub Repository
🌍 Live Website: sm-y.dev

I hope this guide helps you boost your blog’s AX-SEO and AI search visibility! 🚀