Putting the four moves together

A useful way to hold all four in your head:

• Reduce: make what is in the window smaller (compaction first, summarization as a last resort).
• Offload: keep the full data outside the window (on the filesystem) and most actions in the sandbox.
• Isolate: give separate work its own context window via sub-agents, sharing context only when truly needed.
• Retrieve: bring information in on demand for the current step.

None of these requires a smarter model. They are all engineering moves around the model, which is exactly what makes them "context engineering."