Accurately describing the accessibility features of your book gives potential buyers the knowledge they may need to make an informed purchase. It allows readers to know if your e-book meets their needs.
Accessibility can be improved by including alternative text (usually known as ‘alt text’) for screen readers. Alt text is a brief description of the image. Harvard University website has a very useful guide to writing alt text: https://accessibility.huit.harvard.edu/describe-content-images
The method of adding alt text depends on the software used to create the e-book. Generally it involves selecting the image and finding the ‘Alt Text’ or ‘Object Export Options’ setting. For more detailed instructions, consult the guide for your software.
Your e-book’s accessibility and the description can be updated, even after publication.
Find out more about accessibility for e-books here: https://kdp.amazon.com/en_US/help/topic/GBPE3QVZ2J3HLQ4B