Excellent tweet thread about what makes a good alt text to an image or a GIF animation:
I often talk about adding alt text to images, but I never actually talk about what makes good alt text, for people who are unsure. So here's my perspective as a sighted person who sometimes uses a screen reader.
— Kit (Metaphors and Moonlight) (@whykristenburns) May 8, 2021
Tips for writing alt text for images and gifs: