Get in touch with about right legal agreement (8)
I believe the answer is:
contract
'legal agreement' is the definition.
'get in touch with about right' is the wordplay.
'get in touch with' becomes 'contact' (I've seen this before).
'about' means one lot of letters goes inside another.
'right' becomes 'r' (common abbreviation).
'contact' placed around 'r' is 'CONTRACT'.
(Other definitions for contract that I've seen before include "Agree - reduce" , "Promise" , "Agree - get smaller" , "Shrink in legal agreement?" , "Make smaller" .)