Wolf, 24, is a native of Dusseldorf, Germany, who has spent the past three seasons with the Hamburg Freezers of the German League (DEL).
In 48 games this season, Wolf scored 14 goals and 40 points and had a plus-14 rating. He has 44 goals and 115 points in 154 career games with the Freezers.
Wolf has also represented Germany at the World Under-18s, World Junior Championship and German's National Team for Olympic qualifying.
In other signings Monday:
Summers had two goals, one assist and 15 penalty minutes in 18 games this season with the Coyotes. He had two goals, seven assists and 47 penalty minutes in 48 games with Portland of the American Hockey League.
Summers, a first-round pick (No. 29) by the Coyotes in the 2006 NHL Draft, has two goals, four assists and 39 penalty minutes in 47 career NHL games.