Only a silver lining is too little (6)
I believe the answer is:
meagre
'too little' is the definition.
'meagre' can be an answer for 'little' (I've seen this before). I am unsure of the 'too' bit.
'only a silver lining' is the wordplay.
'only' becomes 'mere' (I've seen this in another clue).
'a silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'lining' means one lot of letters goes inside another.
'mere' going around 'ag' is 'MEAGRE'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for meagre that I've seen before include "Inadequate, scanty" , "Scanty, not plentiful" , "Scanty in amount - puts me in rage" , "Thin, lacking quality" , "Thin -- inadequate" .)