The first thing you need to find out is how heavily crevassed the glacier is, and whether any crevasses are likely to be big enough to fall into. Crevasses can be hidden by snow, so people can fall into them unexpectedly.
If you have reliable information that there are no crevasses big enough to fall into, then the use of ice axes and crampons is decided by all the same factors as in any snowy mountain environment, such as ice, exposure, steepness of the slope, and whether or not there is a boot track already.
If falling into a hidden crevasse is a possibility, then you need to do a lot more than just bringing ice axes and crampons. Crevasse self-rescue is a complicated technical topic. You need to learn it from a competent instructor and practice all the techniques extensively before you go. You will travel in a rope team, and every member of the team needs to have both the gear and the skills, because if someone falls in, it's unpredictable who will fall in, who will need to stay in self-arrest position, and who will need to get out of self-arrest and begin setting up the rescue. In addition to the group's rope and any additional rescue lines carried in packs, the minimum gear that each person needs to have on them would be something like the following:
- ice ax
- at least one ice screw
- at least one picket
- 2 shoulder-length slings
- 3 locking biners
- 4 nonlocking biners
- 2 Prusiks
- chest harness
The standard mountaineering textbook Freedom of the Hills has a chapter on glacier travel.