I'm working with a diffusion-based renderer whose inference entry accepts a seed argument. I render the same input twice with two different seeds, and the two outputs come out byte-identical — I confirmed it with a per-frame hash comparison, not just by eye. So either the path is genuinely deterministic, or the seed is accepted and then never consumed by the sampler. How do practitioners verify this? Is there a standard probe — for example, checking which RNG stream the sampler actually draws from, or a minimal seed-sensitivity test where you change one thing and expect the output to move? I want to know whether my seed path is real before I assume the renderer is deterministic. What has worked for you to tell these two cases apart?