Your blog for today should detail the problem you are tackling, and (to the best of your ability) the code that you believe you will be interfacing with.
In this regard, your post should (probably/possibly) include:
In other words, your research should take you into the details of the problem.
When you swim the surface of a pool, you learn the width and breadth of it. It becomes a space you have an overview of.
When you dive to the bottom to retrieve a penny, you learn one path through the pool, though you may have never traveled the entire space.
Your problem decomposition is about that deep dive. You’re attempting to understand the details of the single problem, and what you’re going to need to know to tackle it specifically.