Here is the full list of all 12 Code Tracer achievements.
clear the stage for the first time.
get the silver medal for the first time.
get the gold medal for the first time.
clear the area01 boss stage.
clear the area02 boss stage.
clear all stages in area01.
clear all stages in area02.
stopped 50 bombs in total.
stopped 100 bombs in total.
stopped 300 bombs in total.
stopped 500 bombs in total.
stopped 1000 bombs in total.