A thoughtful intention (4)
I believe the answer is:
idea
'intention' is the definition.
(idea is a kind of intention)
'a thoughtful' is the wordplay.
I cannot really see how this works, but
'a' is found in the answer.
The remaining letters 'ide' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for idea that I've seen before include "It comes to mind" , "Thought; concept" , "Fancy" , "Aim" , "Theory" .)