Overview
Context is only one part of system cost. Model selection is another.
Using the strongest model for every action can be wasteful. Many tasks do not require frontier-level reasoning.
A simple classification task may only need to place an item into one of several categories. A lightweight model can perform that work.
A research or enrichment task may require more reasoning and justify a mid-tier model.
A difficult architectural decision, routing decision, or high-stakes review may justify the strongest model.
The operating principle is to concentrate expensive intelligence where it creates the most value.