A barrel/bundle of laughs British informal Compound
To be funny, hilarious, and pleasant
John is a hilarious guy with many jokes. He's actually a bundle of laughs.
When I'm around with Linda, I always have so much fun. She's a barrel of laughs.
In this context, the expression started life as 'a barrel of fun' -' barrel' just means 'a lot of'. In documents found in the USA, it is first quoted. An early example is this entry in the 1890 edition of Dialect Notes, under the heading 'A Word List from Montana'.
If you swallow the bait, you take something that someone offers you, or agree to do something that someone asks you to do without knowing that it is a trick or way of getting something from you.
You can't just do whatever he wants you to do. Don't swallow the bait.