Normally a check of HP turbine blades for cracking bits missing etc, depending on why you are doing it, you may also need to check IP/LPT and/or Compressor blades. Also in case of RR 211 combustion liner for damage/missing bits etc. MM lays down what you are allowed missing/cracked, good guide is cooling holes on RR RB21-524 HPT blades are 2mm apart.
You'd be surprised on some of the allowable damage limits.