> For the complete documentation index, see [llms.txt](https://script-and-theory.gitbook.io/all-in-one-commerce-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://script-and-theory.gitbook.io/all-in-one-commerce-docs/checkout-blocks/blocks.md). # Blocks * This category allows you to add and configure various functional blocks that can be placed on the checkout page. These blocks include features like upsells, gift options, address validation, and other customizable functionalities that help to enhance the checkout experience. You can easily drag and drop blocks into the checkout customizer page, allowing you to tailor the page according to your store’s needs. * **Key Features:** 1. Upsell blocks to encourage customers to add more products. 2. Gift product options, including gift wrapping and personalized messages. 3. Address validation tools to ensure customers provide correct shipping information. * **Checkout Extension Blocks - Features Overview** The Checkout Extension Blocks offer various functionalities to enhance the checkout page, helping increase sales, improve customer experience, and streamline the purchasing process. Below is an overview of each extension block, how to enable it, and how to use it. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## 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, and the optional `goal` query parameter: ``` GET https://script-and-theory.gitbook.io/all-in-one-commerce-docs/checkout-blocks/blocks.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. 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.