The most common and most likely answer to this crossword clue is the 8 letter word SCHEMING
I've seen this crossword clue in Financial Times
S
C
H
E
M
I
N
G
Buddy explains!

The straight part
We know that "Crafty" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case crafty = scheming.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 SCHEMING mean?
SCHEMING verb- To plot, or contrive a plan.
- To plan; to contrive.
- Tending to scheme; forming underhand plots.
- The activity or practice of making secret or underhanded plans.