I've have two fairly small raised beds for about five years to which I add a few bags of B&Q compost about now. I usually grow carrots, spinach, beans etc.
Should I carry on adding compost as usual or would you recommend some sort of conditioner/fertiliser ?
No expert but, if the beds are full I'm unsure what benefit adding more bulk gives. You'd eventuality have to remove what's there to make room. I'd suspect that most of the time adding nutrients would suffice.