You are doing yourself a disservice by talking about "primitives" and "call state" without naming the actual, industry-standard mechanism you have built.
This is an ACD. In the cloud. Using common terminology gives other developers a reference point in which to do more research and draw their own conclusions about the technology. Even a reference and link to Wikipedia would be good -- the ACD page is lucid [1], and I understood exactly what an ACD does after reading that. I don't get the same sense about TaskRouter from the blog post.
You have a decent explanation of an ACD mechanism, but now telecom-inexperienced developers have to try and internalize your meaning without the benefit of knowing the precise jargon, and potentially missing out on the decades of experience others have had in this field.