The trouble with No Code is that your first paragraph is already my job description: I plan out and document and refine the structure of a problem and its architectural solution while simultaneously developing the system itself. The "sufficient explanation of the goals/problem" is the code—anything less is totally insufficient. And once I have the code, it is both the fully-documented problem and the spec for the solution.
I won't pretend to know the final end state for these tools, but it's definitely not that engineers will write natural-language specs and the LLMs will translate them, because code (in varying degrees of high- and low-level languages) is the preferred language for solution specification for a reason. It's precise, unambiguous, and well understood by all engineers on a project. There is no need to be filled by swapping that out with natural language unless you're taking engineers out of the loop entirely.