Benzotriazole works with all developers as an antifog agent. As mentioned above, it helps with development fog and fog caused by aging. It tends to cool print tones very slightly. It is said to increase contrast a bit, but I have not seen this. Potassium bromide is a less effective antifog agent, but it still has that effect. It tends to warm tones a bit, depending a lot on the paper and the developer it is used in.