I reported chasing dog with no lead - what a sight! (5,3)
I believe the answer is:
eagle eye
'what a sight' is the definition.
(I have seen 'Keen sight' mean 'eagle eye' so perhaps 'sight' could also mean 'eagle eye')
'i reported chasing dog with' is the wordplay.
'reported' shows a homophone (sound like).
'chasing' means one lot of letters go next to another (some letters chase after others).
'dog with' becomes 'eagle' (I can't justify this - if you can you should believe this answer much more).
'i' is a homophone of 'eye'.
'eye' put after 'eagle' is 'EAGLE-EYE'.
'no lead' acts as a link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for eagle eye that I've seen before include "Keen sight" , "Ability to observe fine detail" , "one envisages a long way off" , "Critical inspection" , "Keenness of vision" .)