out_of_stock
The quantity asked for can't be fulfilled. If the product is meant to be bought on backorder, turn on "Continue selling when out of stock" for the variant. Otherwise make sure the agent catalog shows it as sold out, so agents don't offer it in the first place. A mismatch between the stock agents see and the stock checkout uses usually means inventory is tracked at a location that doesn't fulfil online orders.
The cart comes back without the product
Sometimes the cart is created but the line is silently dropped. That usually points to the same causes as item_unavailable, or to an app that edits carts, such as a bundle or upsell app, removing lines it doesn't recognise.
Find which products fail
The AI shopping readiness checker puts up to three of your products in a real agent cart (and cancels it) and shows the store's refusal code for each one that fails. The full audit does the same across a 25-product sample.
The checks behind this guide
Agents can't add it to a cart
An agent that finds the product can't buy it: the store refuses to put it in the agent's cart, so assistants that shop for people, such as Claude Duet, move on to a store that sells it.
How to fixCheck the variant in Shopify admin: it has to be active, in stock or set to keep selling, and available in the market and sales channels agents buy through. Purchase options that need a selling plan or a minimum quantity also block a one-unit cart.
Missing from the catalog AI agents shop from
Agents that shop Shopify stores over the Universal Commerce Protocol look the product up and get nothing back, so they can't recommend or sell it.
How to fixCheck the product's status and sales channels in Shopify admin: it has to be active and published to the channels Shopify's catalog for agents draws on. Draft, unlisted or channel-excluded products are invisible to agents.
Questions
Does testing a cart create an order or email the customer?
No. A cart is not an order and has no buyer details, so nothing is charged or sent. The agent check cancels each cart as soon as it has read the result.
My product shows in stock on the website. Why does the agent get out_of_stock?
The website and the agent cart can draw on different markets and locations. Check that the variant has stock at a location that fulfils online orders and is sold in the market the agent's cart uses.
Updated 2026-10-22. catalogaudit isn't affiliated with Shopify or Anthropic.