Following up on their signing of utility infielder Rob Mackowiak over the weekend, the Mets added pitchers Kyle Snyder and Jon Switzer with minor-league deals tonight. Snyder, a right-hander, had two appearances for the Red Sox in 2008 after going 2-3 with a 3.81 ERA in 46 relief appearances two years ago. Switzer, a lefty, last pitched in the major leagues with Tampa Bay in 2007.