DANCE

Agnes de Mille’s first ballet for the American Ballet Theater in 13 years opened Tuesday in New York, prompting an outpouring of praise for the 82-year-old choreographer. The company’s artistic director, Mikhail Baryshnikov, read a congratulatory telegram from the Reagans and one from Sen. Edward M. Kennedy (D-Mass.) at a reception for de Mille at the Metropolitan Opera before the performance began. “The Informer,” which had its Los Angeles premiere March 15, is set during political turmoil in Ireland between 1916 and 1921.