--- title: AEO & GEO description: How the storefront makes itself legible to AI answer engines and generative search, with built-in content negotiation, structured data, and discovery surfaces. type: guide --- # AEO & GEO # AEO & GEO **Answer Engine Optimization (AEO)** and **Generative Engine Optimization (GEO)** are the practices of making a site legible to the AI surfaces that increasingly mediate commerce — ChatGPT, Claude, Perplexity, Google AI Overviews, and the long tail of agent-driven shopping. Where classical SEO optimizes for crawlers that build a search index, AEO/GEO optimizes for models that read a page once and synthesize an answer. The legibility bar is higher: noisy markup, hydration-only data, and content trapped behind interaction all degrade an LLM's ability to recover the underlying facts. The template ships with several built-in surfaces that contribute to AEO/GEO. The largest of them is **content negotiation** — serving structured markdown to clients that ask for it — but the supporting cast (JSON-LD schema, sitemaps, OpenGraph metadata) is what makes a page consistently parseable across surfaces. ## Surfaces in the template | Surface | What it does | Key files | | -------------------------------- | ------------------------------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------------- | | **Content negotiation** | Serves clean markdown to AI clients via `Accept: text/markdown` | `next.config.ts`, `app/md/**`, `lib/markdown/**` | | **Schema.org JSON-LD** | Embeds structured `Product`, `BreadcrumbList`, and `Organization` data | `components/product-detail/schema.tsx`, `components/schema/**` | | **Sitemap** | [Sitemap index + paged children](/docs/anatomy/sitemap) for products and collections | `app/sitemap.xml/route.ts`, `app/sitemap/[shard]/route.ts` | | **Robots** | Declares crawl policy and blocks faceted (sort/filter) collection URLs | `app/robots.ts` | | **`llms.txt`** | Curated `/llms.txt` index of collections and discovery links for AI agents | `app/llms.txt/route.ts`, `lib/markdown/llms.ts` | | **OpenGraph & Twitter metadata** | Per-route title/description/image previews, plus `product` OG tags (type, price, availability) on PDPs | `lib/seo.ts`, `components/product-detail/open-graph.tsx`, route-level `generateMetadata` | The rest of this page goes deep on content negotiation. The other surfaces are documented inline in the linked files. ## Content Negotiation Product, collection, and search pages serve structured markdown when clients send `Accept: text/markdown`. Browsers continue to receive HTML; AI agents and crawlers get clean, parseable markdown from the same URL. This is built in and requires no configuration. Every markdown route lives under a single top-level `app/md/` directory so all content-negotiation handlers are co-located and easy to find. ### How it works ``` GET /products/speaker (Accept: text/markdown) GET /collections/speakers (Accept: text/markdown) GET /search?q=speaker (Accept: text/markdown) ↓ next.config.ts rewrite ↓ /md/products/[handle] /md/collections/[handle] /md/search ↓ Route handler response: text/markdown ``` Browsers that don't send `Accept: text/markdown` are unaffected — the rewrite only fires when the header matches. ### Testing ```bash # Returns structured markdown curl -H "Accept: text/markdown" http://localhost:3000/products/speaker # Returns collection markdown with products, filters, and pagination curl -H "Accept: text/markdown" http://localhost:3000/collections/speakers # Returns search markdown with query, filters, and result summaries curl -H "Accept: text/markdown" "http://localhost:3000/search?q=speaker&sort=price-low-to-high" # Returns the normal HTML page curl http://localhost:3000/products/speaker ``` The `Vary: Accept` header ensures CDNs cache markdown and HTML responses separately. ### What's included in the markdown * **Product pages** — handle, brand, category, pricing, options, variants, specs, images, tags, and SEO metadata * **Collection pages** — collection metadata, description, applied filters, available filters, products, pagination, image, and SEO metadata * **Search pages** — query metadata, active collection filter, applied filters, available filters, products, and pagination state ### Key files | File | Purpose | | -------------------------------------- | --------------------------------------------------- | | `next.config.ts` | Rewrite rules matching `Accept: text/markdown` | | `app/md/products/[handle]/route.ts` | Product markdown route handler | | `app/md/collections/[handle]/route.ts` | Collection markdown route handler | | `app/md/search/route.ts` | Search markdown route handler | | `lib/markdown/product.ts` | `productToMarkdown()` converter | | `lib/markdown/collection.ts` | `collectionToMarkdown()` converter | | `lib/markdown/search.ts` | `searchResultsToMarkdown()` converter | | `lib/markdown/catalog.ts` | Shared product/filter/pagination formatting helpers | | `lib/markdown/utils.ts` | Formatting helpers (prices, tables, escaping) | ### Multi-locale If you have enabled Shopify Markets, the rewrite fires before locale routing — no additional configuration is needed. Pass a `?locale=` query parameter to the markdown endpoint for locale-specific pricing and collection/search context. ## llms.txt `/llms.txt` is a curated, machine-readable index of the storefront — an [emerging convention](https://llmstxt.org) that is to AI agents what `robots.txt` is to crawlers. It links to the search entry point, the collection catalog, and the sitemap/robots discovery surfaces, and tells agents that those pages also serve clean Markdown under `Accept: text/markdown` (the content negotiation above). The route is dynamic: collections are pulled live from Shopify and capped so the file stays a concise index rather than an exhaustive dump — the full URL set lives in the [sitemap](/docs/anatomy/sitemap). Because the links honor content negotiation, the virtual `/collections/all` catalog page is served as Markdown too, not just HTML. ### Key files | File | Purpose | | ----------------------- | ------------------------------------------------------------ | | `app/llms.txt/route.ts` | Route handler; fetches collections and serves `text/plain` | | `lib/markdown/llms.ts` | `llmsTxt()` generator that builds the index from the catalog | --- For a semantic overview of all documentation, see [/sitemap.md](/sitemap.md) For an index of all available documentation, see [/llms.txt](/llms.txt) For agent-facing discovery, including API and MCP surfaces, see [/agents.md](/agents.md)