SKU.md
A simple, open draft for AI-readable product catalogs,
built for merchants to publish themselves.
Think of SKU.md as a catalog brief for agents: one predictable place to discover categories, representative products, policies, AI usage, and the live data sources behind them.
---schema_version: "sku.md/1.0"site_name: "Example Outdoor Gear"site_url: "https://www.example-outdoor.com"last_updated: "2026-07-16T08:00:00+08:00"update_frequency: "weekly"languages: ["zh-CN", "en-US"]currency_default: "USD" ai_usage: training: "disallow" retrieval_answer: "allow" citation_required: true agentic_checkout: "unsupported" capabilities: self_hosted: schema_jsonld: status: "live" note: "每个商品详情页 <head> 内嵌 schema.org/Product + Offer JSON-LD，含实时价格与库存状态" # Additional capabilities follow---Why SKU.md?
llms.txt maps a whole site. Product JSON-LD, sitemaps, and commerce feeds carry detailed or live product data.
SKU.md fills the layer between them: a concise catalog overview with product context, policies, AI permissions, and pointers to the sources an agent should trust next.
It is intentionally separate to:
Give agents one predictable, merchant-controlled catalog summary.
Keep descriptions factual while live price and stock stay in real-time sources.
Declare what is self-hosted, platform-gated, live, planned, or unsupported.
The draft does not replace any protocol in the commerce stack. It makes their roles and availability easier to discover from one open, self-published file.
One SKU.md connects the commerce stack
SKU.md does not replace existing standards. It tells agents which layers a merchant publishes and where to find them.
Examples
---schema_version: "sku.md/1.0"site_name: "Example Outdoor Gear"site_url: "https://www.example-outdoor.com"last_updated: "2026-07-16T08:00:00+08:00"update_frequency: "weekly"languages: ["zh-CN", "en-US"]currency_default: "USD" ai_usage: training: "disallow" retrieval_answer: "allow" citation_required: true agentic_checkout: "unsupported" capabilities: self_hosted: schema_jsonld: status: "live" note: "每个商品详情页 <head> 内嵌 schema.org/Product + Offer JSON-LD，含实时价格与库存状态" sitemap: status: "live" url: "https://www.example-outdoor.com/sitemap-products.xml" webmcp: status: "unsupported" scope: "/products/*" tools: [] platform_gated: acp_product_feed: status: "planned" url: "https://www.example-outdoor.com/feeds/acp-products.jsonl.gz" acp_checkout: status: "unsupported" ucp_catalog: status: "planned" well_known: "https://www.example-outdoor.com/.well-known/ucp" ucp_checkout: status: "unsupported" contact: business_email: "support@example-outdoor.com" merchant_of_record: "Example Outdoor Gear Inc."--- # Example Outdoor Gear > 专注轻量化户外装备的独立站：帐篷、睡袋、登山包三大品类，主打> 750g 以下轻量化设计，产地为越南与中国代工厂，价格区间 $39–$459。 ## Categories - [轻量化帐篷 / Tents](https://www.example-outdoor.com/collections/tents): 12 款在售，重量 1.1–2.3kg，价格 $129–$459- [羽绒睡袋 / Sleeping Bags](https://www.example-outdoor.com/collections/sleeping-bags): 8 款在售，适温 -5°C 至 10°C，价格 $89–$329- [登山背包 / Backpacks](https://www.example-outdoor.com/collections/backpacks): 15 款在售，容量 20L–65L，价格 $39–$189 ## Featured SKUs | SKU ID | 名称 | 关键规格（事实密度） | 参考价区间 | 商品页 | 详情数据 ||---|---|---|---|---|---|| TENT-ULT-02 | UltraLight 2P 双人帐 | 重量 1.35kg，20D 尼龙硅涂层，静水压 3000mm，含地钉 8 根 | $259–$299 | [详情](https://www.example-outdoor.com/products/tent-ult-02) | JSON-LD 内嵌 || BAG-DOWN-700 | 700 蓬松度羽绒睡袋 | 适温下限 -5°C，重量 890g，90/10 白鹅绒，防水外层 | $199–$249 | [详情](https://www.example-outdoor.com/products/bag-down-700) | JSON-LD 内嵌 || PACK-45L-AIR | Air 系列 45L 背包 | 空载重量 980g，铝合金背负系统，含防雨罩 | $129–$159 | [详情](https://www.example-outdoor.com/products/pack-45l-air) | JSON-LD 内嵌 || TENT-SOLO-01 | Solo 单人帐 | 重量 890g，一体式外帐内帐，抗风 8 级 | $189–$219 | [详情](https://www.example-outdoor.com/products/tent-solo-01) | JSON-LD 内嵌 || BAG-SYN-COMFORT | 化纤填充舒适睡袋 | 适温下限 5°C，重量 1.2kg，适合新手/湿润气候 | $89–$109 | [详情](https://www.example-outdoor.com/products/bag-syn-comfort) | JSON-LD 内嵌 | *完整 SKU 列表与实时价格/库存请参考 `sitemap-products.xml` 或商品详情页 JSON-LD，本表仅为精选摘要，可能不含最新上下架变动。* ## FAQ **Q: 发货需要多久？**A: 中国大陆仓当日发出，标准物流 7–12 个工作日送达美国/欧洲；提供物流单号查询。 **Q: 支持退换货吗？**A: 收货后 30 天内未拆封可无理由退换，运费由买家承担；质量问题由卖家承担双程运费。 **Q: 帐篷/睡袋有防水认证吗？**A: 帐篷外帐静水压均 ≥ 3000mm，达到国标轻装备防水线；具体数值见各商品详情页规格表。 **Q: 是否支持 AI 购物助手直接下单？**A: 目前不支持（见 `ai_usage.agentic_checkout: unsupported`）；请引导用户前往商品页完成购买。 ## Policies - Shipping: 中国大陆仓发货，标准物流 7–12 个工作日，支持全球主要国家- Returns: 30 天无理由退换（未拆封），质量问题免运费退换- Warranty: 帐篷/背包主体 1 年质保，睡袋 6 个月质保 ## Changelog - 2026-07-16: 初始发布，覆盖三大品类共 35 个 SKU，精选 5 个代表商品 Root catalog
A concise site-wide catalog at /sku.md with categories, selected products, policies, and data pointers.
Category catalog
Optional nested files let large catalogs publish fresher, category-specific guidance with nearest-file precedence.
AI usage
Required declarations make training, retrieval, citation, and agentic checkout boundaries explicit.
Capabilities
One manifest distinguishes self-hosted product data and actions from platform-gated feeds and checkout.
How to use SKU.md?
1. Prepare live product truth
Publish Product and Offer JSON-LD on product pages and maintain a product sitemap. SKU.md summarizes the catalog; these sources remain authoritative for live details.
2. Add /sku.md
Create a UTF-8 Markdown file at the site root with the required frontmatter, categories, representative products, FAQs, policies, and changelog.
3. Make it discoverable
Allow root and nested sku.md paths in robots.txt, add a SKU Catalog link to llms.txt, and optionally expose a sku-catalog link element on product pages.
4. Keep it current, then split only when needed
Update capability status and catalog summaries on the declared cadence. Add category-level sku.md files only when catalog size, update cadence, or capability differences justify them.
About
SKU.md is an original open draft informed by established discovery and commerce mechanisms, including robots.txt, llms.txt, Schema.org, WebMCP, ACP, and UCP.
Version 1.1 is a draft proposal, not a formally adopted standard. Its goal is to make a practical merchant-controlled catalog summary available today while keeping live commerce truth and transaction authority in the systems designed for them.
FAQ
Is SKU.md an official standard?
No. sku.md/1.0 is an original proposal, not an industry-adopted standard. The draft is published openly so merchants, platforms, and agent builders can evaluate and improve it.
Are there required fields?
Yes. The draft requires schema_version, site identity, last_updated, the complete ai_usage group, and the capabilities manifest. Missing capabilities should be declared as unsupported instead of being omitted.
Should price and inventory go in SKU.md?
No. SKU.md should point to live product pages, Product and Offer JSON-LD, sitemaps, or approved feeds. Keeping volatile values out of the summary reduces the chance that an agent quotes stale commerce data.
Does SKU.md enable agentic checkout?
Not by itself. It only declares whether ACP or UCP checkout is live, planned, or unsupported. Checkout still requires the relevant platform integration, merchant approval, and real-time transaction flow.
How do category files inherit settings?
A nested category sku.md inherits ai_usage and capabilities from the root file unless it explicitly overrides them. The nearest file applies, while every nested file maintains its own last_updated value.
How often should I update it?
Update it when categories, policies, representative products, or capability status changes. Declare daily, weekly, or on-change in update_frequency, and record structural revisions in the changelog.
How do agents discover SKU.md?
Serve it at the site root, allow root and nested sku.md paths in robots.txt, add a SKU Catalog link to llms.txt, and optionally expose a sku-catalog link element on product pages.
<link rel="sku-catalog" href="/sku.md">