Defining An Activity

(define-activity TRACE-WALK
  :documentation "Traces the Web Walking activity."
  :constraint-set ((no-cycles)(depth 2)
                   (header-robots-allowed))
  :actions ((trace) (trace-headers)
            (walk-inferiors))
  :operator "JCMa@ai.mit.edu"            
  :report-stream *standard-output*)