The American Guild of Musical Artists has filed an unfair-labor-practice complaint against the San Francisco Opera. In February the companay, which is having big money problems, announced it was cutting its annual Western Opera Theater tour because “the costs, scope and purpose of the Western Opera Theater tour were no longer in line with the Opera Center’s need for fiscal responsibility.” The union says that the company violated the National Labor Relations Act “by taking such action without prior notice to or bargaining with the union.”