Minimum of documentation for distributed run-time

In GitLab by @pdamme on Jul 30, 2021, 19:06

Our first distributed run-time, which was contributed by !21, still lacks a minimum of documentation. To ease understanding of the code for everyone, there should at least be a short summary (can be a single sentence) for each class and major function, representing its purpose.

The issue concerns the distributed run-time contributed by !21, but names no files or tests. Locate that run-time's classes and major functions, then read their surrounding code to summarize each purpose. Done means every class and major function has at least a short purpose summary.

Written by the indexing model from the issue text.