full of beans

1. Lively, energetic, in high spirits, as in The children were full of beans today, looking forward to their field trip . This expression has no valid explanation. [c. 1840]

2. Also, full of prunes . Acting foolish, talking nonsense, as in One cup of coffee won't hurt you—you're full of prunes . [c. 1930] Also see full of crap .

Example Sentences

“He works for us as a detection dog. When he works he’s really focused and works really well but when he’s off work he’s a two-year-old Labrador, full of beans, jumping around.”

From BBC

During a service of thanksgiving, Rachel Simpson's sister Cher described her as “full of beans, funny faces, and warm embraces”.

From BBC

She said she remembers Daniel as "an enigma, full of beans, full of life, from the day he was born just kind, caring, generous, loved by everybody."

From BBC

“Look: I made a joke. Get it? Full of beans?”

From Literature

The six-times champion trainer is full of beans despite surprisingly poor record in race he has never won.

From BBC