Doesn't matter how mundane or boring the job is.
If your job is to shuck oysters, then your self evaluation should be how well, how fast, and how accurately you shucked oysters. It should include whether you helped teach others to do so better than they did before, and whether you figured out a way to do so on your own behalf. It should also include whether you figured out how to make more money or cut other costs while you were doing your job, and whether you did anything that would reflect well on the company with its customers or potential customers.