Reposting this amazing mini-guide on how to write helpful alt text created by @Veron4ica (source: https://veroniiiica.com/how-to-write-alt-text-image-descriptions-visually-impaired/) and found via @karengregory (including Karen's original image description) so that I can pin it.
As some pointed out, the example alt text could be improved for folks not too familiar with capybaras, or yuzu fruits.
Something like this might work:
"A capybara, a large rodent animal with brown fur, sitting in water, with its head poking out, looking relaxed.
Yellow yuzu fruits, a citrus fruit similar to lemons, are floating in the water, and one is balanced on top of the capybara's head."
Still, very much following this guide. Good reminder to always keep your audience in mind!
Alt Text Hall of Fame