The phrase "a sharp sketch of" is correct and usable in written English.
It can be used to describe a concise and clear representation or outline of a subject or idea.
Example: "The author provided a sharp sketch of the main themes in her novel, making it easy for readers to grasp the core messages."
Alternatives: "a clear outline of" or "a vivid depiction of".
In "Delinquent Missive," for example, the poet begins with a quick, sharp sketch of her subject, a convicted killer doing hard time, in a way that recalls her unacknowledged master, Gerard Manley Hopkins, who also used prayer as a booster rocket for poetry rather than a replacement for it.
He excavates the deep history of the "war" on cancer, weaving haunting tales of his own clinical experience with sharp sketches of the sometimes heroic, sometimes misguided scientists who have preceded him in the fight.
Brief, wordless scenes of Dwight hunkering under a boardwalk, scavenging for food in dumpsters, and sleeping in a rust-bitten Pontiac (the "blue ruin" of the title) provide sharp thumbnail sketches of a passive itinerant lifestyle, while a haunting tableau of Dwight shut out of a thriving fun park vividly depicts his isolation from the joyfully illuminated throng of carefree Delaware society.
Brief, wordless scenes of Dwight hunkering under a boardwalk, scavenging for food in dumpsters, and sleeping in a rust-bitten Pontiac (the "blue ruin" of the title) provide sharp thumbnail sketches of a passive itinerant lifestyle, while a haunting tableau of Dwight shut out of a thriving fun park vividly depicts his isolation from the joyfully illuminated throng of carefree Delaware society.
There is a sharp intake of breath.
This is a sharp change of attitude.
"He had a sharp sense of humor.
Finkelstein is a sharp critic of Israel.
A sharp pair of scissors.
There are also sharp character sketches – of the oily foreign minister and later chancellor Bernhard von Bülow, for example, a sort of poor man's Bismarck who demanded a German "place in the sun", or Britain's energetic First Sea Lord, "Jacky" Fisher, who took his pleasures from the Old Testament, dancing and naval efficiency.
