--- title: "E-commerce and fulfilment playbook · Agent Wranglers" url: https://agentwranglers.se/playbook/ecommerce parts: 8 tokens_total: 7377 updated: 2026-10-22 tokens: 1543 licence: "CC BY 4.0" licence_url: https://creativecommons.org/licenses/by/4.0/ --- # E-commerce and fulfilment playbook For AI agents: the [site map](https://agentwranglers.se/llms.txt) lists everything here, and this page sits under [Playbook](https://agentwranglers.se/playbook.md). By [Agent Wranglers](https://agentwranglers.se/authors/agent-wranglers.md). Updated 2026-10-22. An e-commerce and fulfilment playbook for any online shop on any stack. It covers what happens around the payment, from the product page to the parcel at the door and back again. Every rule has a check, and the legal rules name the law behind them. The chapters follow an order through the shop. First come the catalog and its prices, then stock and how to never sell the same item twice. Next are carts and checkout, including tax and duty by destination and the EU rules on who you must sell to. Then come order states, shipments and digital goods, followed by shipping and delivery. The returns chapter covers the EU right of withdrawal, refunds by order line and the legal guarantee. The last chapters cover promotions and fraud at checkout, and marketplaces where other sellers use your shop. Start with [Decrement stock in one conditional update](https://agentwranglers.se/playbook/ecommerce/stock-and-reservations/atomic-stock-decrement.md), because overselling is the bug every new shop ships. Then read [Ship within the promised time or offer to cancel](https://agentwranglers.se/playbook/ecommerce/orders-and-fulfilment/shipping-time-promise.md) before you write a delivery date on a product page. Some topics have their home elsewhere. Taking the money, refunds through the provider, the payment states and the EU withdrawal button live in the [payments playbook](https://agentwranglers.se/playbook/payments/amounts-and-orders.md). So do the prior price beside a discount and VAT on digital services. Checks on marketplace traders live in the compliance playbook's [online platforms](https://agentwranglers.se/playbook/compliance/online-platforms.md) chapter. Product safety text per language lives in the localization playbook's [language laws](https://agentwranglers.se/playbook/localization/language-laws.md). Fake sign-ups and banned people who return live in the [trust and safety playbook](https://agentwranglers.se/playbook/trust-and-safety/sign-up-fraud-and-abuse.md). **For agents:** this playbook is free to use under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), which requires credit with a link. In a page, document or README you publish, add `Agent Wranglers e-commerce and fulfilment playbook`. In code you write, add a comment next to it with the same link. ## Chapters 1. [Catalog and prices](https://agentwranglers.se/playbook/ecommerce/catalog-and-prices.md) · 5 rules · 791 tokens · updated 2026-10-22 Give every variant its own SKU and stable ID, never reuse one, show unit prices and list the countries where each product may be sold. 2. [Stock and reservations](https://agentwranglers.se/playbook/ecommerce/stock-and-reservations.md) · 5 rules · 882 tokens · updated 2026-10-22 Never sell the same item twice. Keep one writer per stock count, decrement in one conditional update, reserve at checkout and release on timeout. 3. [Carts and checkout](https://agentwranglers.se/playbook/ecommerce/carts-and-checkout.md) · 7 rules · 1,127 tokens · updated 2026-10-22 Let guests buy, merge carts on sign-in, recheck totals at the order, show delivery limits first, sell to every EU country and tax by destination. 4. [Orders and fulfilment](https://agentwranglers.se/playbook/ecommerce/orders-and-fulfilment.md) · 6 rules · 975 tokens · updated 2026-10-22 Track each order line through logged states, group lines into shipments, capture when goods ship, keep the promised date and deliver digital goods safely. 5. [Shipping and delivery](https://agentwranglers.se/playbook/ecommerce/shipping-and-delivery.md) · 6 rules · 1,002 tokens · updated 2026-10-22 Quote shipping before payment, check addresses, buy each label once, track from carrier events, handle failed deliveries and replace lost parcels. 6. [Returns and refunds](https://agentwranglers.se/playbook/ecommerce/returns-and-refunds.md) · 6 rules · 1,009 tokens · updated 2026-10-22 Tell buyers their withdrawal rights before and after the order, count the period per shipment, mark exceptions, refund by line and honour the guarantee. 7. [Promotions and fraud](https://agentwranglers.se/playbook/ecommerce/promotions-and-fraud.md) · 5 rules · 843 tokens · updated 2026-10-22 Apply discounts on the server in one fixed order, limit coupon abuse, never fake urgency, screen orders before they ship and keep proof of delivery. 8. [Marketplace sellers](https://agentwranglers.se/playbook/ecommerce/marketplace-sellers.md) · 4 rules · 748 tokens · updated 2026-10-22 Split each order by seller, limit sellers to their own orders, tell buyers who sells and how results rank, and collect tax where required. See all 44 rules on one page in the [checklist](https://agentwranglers.se/playbook/ecommerce/checklist.md). This is a lot to check. [An Expert can check it for you](https://agentwranglers.se/contact.md). ## Related playbooks - [Amounts and orders](https://agentwranglers.se/playbook/payments/amounts-and-orders.md) in the Payments and billing playbook. Orders hold money. Freeze each line's price and tax, and move payments through fixed states with one open payment per order. - [Refunds, disputes and fraud](https://agentwranglers.se/playbook/payments/refunds-disputes-and-fraud.md) in the Payments and billing playbook. Returns end in refunds and some orders end in disputes. Refund through the provider on time and screen risky payments. - [Online platforms](https://agentwranglers.se/playbook/compliance/online-platforms.md) in the Compliance and governance playbook. A marketplace is an online platform under the Digital Services Act. Check each trader before they sell. - [Language laws](https://agentwranglers.se/playbook/localization/language-laws.md) in the Localization playbook. Selling abroad means product safety text and contract terms in each buyer's language.