Demonstrate when party's declaration of intent falls short (8)
I believe the answer is:
manifest
'demonstrate' is the definition.
(I know that demonstrate can be written as manifest)
'declaration of intent falls short' is the wordplay.
'declaration of intent' becomes 'manifesto' (I've seen this in another clue).
'falls short' means to remove the last letter (I've seen 'falling short' mean this).
'manifesto' with its last letter taken away is 'MANIFEST'.
'when party's' acts as a link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for manifest that I've seen before include "Obvious, like ship's cargo list" , "Obvious to the eye" , "Clear, obvious" , "Plain - cargo list" , "list of passengers for customs" .)