To make a sudden, quick critical remark or attack.
Snipes are usually not nice because they are quick and critical.
Examples:
She snipes at everything I do.
He always snipes at my ideas.
When I wear my new dress, she snipes at it.
He snipes at my cooking, but he can't even boil water!
She snipes at everyone, but she can't do anything right herself.
He snipes at my drawings, but his are worse than mine.