Glad that you found them @JulianSMoore, they are a bit hidden
The idea of them is that you can pass any variable from one component to another, and not be limited to just the output.
This is useful in some very niche models or in RL where we at one point wanted to show the reward, action and environment as three different flows.
Right now it’s a bit of a relic feature which we noticed that we implemented before its time. It should still work just fine as the underlying architecture supports sending arbitrary (I think the only requirement is that they are tf objects) values between the components. But we likely won’t do much with that feature for a while as we are focusing more on the groundwork now