---
title: "Overview · Nook docs"
canonical: https://www.checkoutbench.ai/docs
last_updated: 2026-11-03
---

# Overview

> As of Nov 3, 2026, 2:45 PM PST, from Nook main 680daa2f.

Nook is a shopping service for AI agents. An agent developer integrates it once. After that, their agent can take a person's request ("get me two packs of AA batteries from Amazon"), get a checked price from the store's real checkout, and, once the person says yes to that price, place the order.

In the repo's own words: "A shopping service that an agent developer integrates once to turn a user's request into a verified merchant quote and, with the required authority, a confirmed order."

## Who it is for

- **Agent developers** are the current customer. Their agent owns the chat with the person; Nook provides the API and a written guide for the agent.
- A product for **merchants** (retailers) is documented as a possible future option. It is not part of the current build.

## What Nook does

1. **Connects store accounts.** The person signs in to a store once through Nook (by password, a one-time code, the store's other sign-in methods, or an emailed sign-in link). Nook keeps the signed-in session, encrypted, and checks that it still works in a brand-new cloud browser before counting the store as connected.
2. **Prepares a quote.** For each request, a fresh cloud browser restores the person's session, finds the product, adds it to the cart, reads the store's own checkout figures (items, charges, total, address, card) and then puts the cart back the way it was.
3. **Buys only after a human yes.** When the person says yes to the quote's total, the agent sends their words to Nook, which presses the store's final order button once and looks for the store's confirmation. Without those words, the person approves on Nook's own review page.

## How decisions are split

- A choice model called **Jev** picks among products, menu items and options that Nook actually saw on the store's pages.
- Ordinary code does everything else: clicking, arithmetic, checking the checkout against the request, keeping sessions, and cleaning up the cart.
- Every store is reached through browser automation in a real browser, not through official store APIs.

## Status in one paragraph

A person can connect an account at 40 stores and sites: 12 built in and 28 that Nook set up from their web address (see [Supported stores](/docs/stores)). Quotes and purchases work at 6 stores, and DETOURE quotes too. Some sites offer named operations instead, such as Skyscanner's flight search and price alerts. Real purchases have been made. The testing lab at [/lab](/lab/) runs real chat models against production Nook, quote-only by default. Production runs Nook's latest backend release (Nov 2), and every backend change on main is in it. See [Known limits](/docs/limits).

## Pages in these docs

- [Supported stores](/docs/stores)
- [How a request flows](/docs/request-flow)
- [API basics](/docs/api)
- [Testing lab](/docs/lab)
- [Product identity rules](/docs/product-identity)
- [Known limits and open issues](/docs/limits)
- [Changelog](/docs/changelog)