Stoll got a four-year deal, while Richardson signed a two-year contract. Stoll was acquired by the Kings with defenseman Matt Greene from Edmonton in exchange for Lubomir Visnovsky in June. Stoll had 14 goals and 22 assists in 81 games for the Oilers last season. He played on their 2006 team that lost in the Stanley Cup finals.
Richardson was acquired by the Kings from Colorado in June for a second-round selection in this year's NHL entry draft. He had two goals and three assists in 22 regular season games with the Avalanche last season.
He also played 38 games with Lake Erie, Colorado's AHL affiliate, and had 14 goals and 26 assists.
The Kings open training camp Friday under new coach Terry Murray in El Segundo.