No matter what you’re writing, description serves to guide and engage a reader. But description the does not enhance plot, deepen character development, or set tone (i.e. description for the sake of description) bogs writing down.
For example, if two characters are engaged in intense discussion about a personal issue, describing the details of their surroundings — like sharing a greasy plate of curly cheese fries — adds depth. They can help “explain” without you (or your characters) having to editorialize or drown in dull exposition.
On the other hand, a lengthy description of the weather might distract from the emotional struggle (or, of course, it might emphasize it). Wind rustling through the trees is probably extra fluff unless the weather itself underscores or contrasts something else going on or about to go on.
Early drafts often include descriptions of what a character looks like. Is it necessary that readers be told specifically about precise physical appearance? Sometimes yes, but rarely in detail or all at once.
As you edit, consider what the goal of your passage aims toward. Prioritize the descriptive details that serve to promote progress toward that specific goal. Flex your sensory muscles to bring these descriptions forward. Jettison the details that are just…included.
Ask yourself: who cares? and why does it matter? If no good answer appears, then the description is probably just extra verbiage.