Sentence examples for a joker from inspiring English sources

The phrase "a joker" is correct and usable in written English.
It can be used to refer to someone who is playful, humorous, or often makes jokes, typically in a light-hearted context.
Example: "At the party, everyone loved Mark because he was such a joker, always making us laugh with his funny stories."
Alternatives: "a comedian" or "a prankster".