Typical method by which one exploits agent of pest control (6)
I believe the answer is:
mouser
'one exploits agent of pest control' is the definition.
I can't tell whether this definition defines the answer.
'typical method by' is the wordplay.
'typical' becomes 'user' (I can't justify this - if you can you should believe this answer much more).
'method' becomes 'MO' (modus operandi, a particular method).
'by' means one lot of letters go next to another.
'user' put after 'mo' is 'MOUSER'.
'which' acts as a link.
Can you help me to learn more?
(Other definitions for mouser that I've seen before include "Rodent-catching cat" , "Cat proficient at catching small rodents" , "Preying cat" , "moggy" , "Cat as hunter of small rodents" .)