@dualmark/core

Framework-agnostic primitives for AEO (Answer Engine Optimization) infrastructure.

Zero runtime dependencies. ESM + CJS. Strict TypeScript.

Install

bun add @dualmark/core

What's in it

• Content negotiation (parseAcceptHeader, negotiateFormat) — RFC 7231 §5.3.2 compliant
• AI bot detection (detectAIBot, AI_BOTS) — registry of 24 known crawlers with vendor + purpose metadata
• Markdown response (markdownResponse, injectMarkdownAlternateLink) — builds Response objects with all AEO headers
• Path utilities (toMarkdownPath, toMarkdownUrl) — convert HTML paths/URLs to their markdown twins
• Token estimation (estimateTokens) — default is whitespace-split
• Text utilities (normalizeUnicode, cleanBody, slugToTitle, fmtDate, joinLines) — for writing markdown converters
• Composition helpers (listingToMarkdown, renderRelatedLinks, renderFAQSection)
• llms.txt rendering (renderLlmsTxt)

Quick example

import { negotiateFormat, markdownResponse, detectAIBot } from "@dualmark/core";

export default {
  async fetch(request) {
    const accept = request.headers.get("accept") ?? "";
    const ua = request.headers.get("user-agent") ?? "";
    const bot = detectAIBot(ua);
    const fmt = negotiateFormat(accept);

    if (fmt === null) return new Response("Not Acceptable", { status: 406 });

    if (bot.isBot || fmt === "markdown") {
      return markdownResponse("# Hello\n\nThis is the markdown twin.");
    }

    return new Response("<html><body>Hello</body></html>", {
      headers: { "Content-Type": "text/html" },
    });
  },
};

License

Apache 2.0 — see LICENSE.

Spec

This package implements the AEO Specification v1.0.