summary vs succinct

summary is a noun but succinct is not a noun.

Word	Noun	Adjective	Verb	Adverb
summary	Yes	Yes	No	No
succinct	No	Yes	No	No

As adjectives, summary and succinct are synonyms defined as:

Other synonyms of summary include compact, compendious.

summary (noun)	succinct (noun)
a brief statement that presents the main points in a concise form

summary (adjective)	succinct (adjective)
briefly giving the gist of something	briefly giving the gist of something
performed speedily and without formality