What is measured
The audit inspects every img: a missing attribute reduces coverage and an empty value is recorded separately.
Content and images
Image alternative text
This check counts images without an alt attribute and distinguishes them from intentionally decorative images with empty alt.
Pass criterion
Informative images have concise functional alt text, while decorative images use alt="".
What to fix
Describe the image’s meaning or action without keyword stuffing and avoid repeating adjacent copy verbatim.
Automation limit
Automation sees whether alt exists but cannot guarantee that the wording is accurate or useful.
Reference