The most common and most likely answer to this crossword clue is the 6 letter word ETUDES
I've seen this crossword clue in The Guardian
E
T
U
D
E
S
Buddy explains!

The straight part
We know that "works" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case works = etudes.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ETUDES mean?
ETUDES noun- A short piece of music, designed to give a performer practice in a particular area or skill.