# Carts Whisk uses the notion of a persistent Cart which we have stored on our site for 7 days and you can reuse by its `id` across all of your client apps. Because Cart has state, you can add items and recipes into it, and get alternative product options from the selected retailers and manage from different clients. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.whisk.com/master/api/carts.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.