In one line: the context window is a workbench, not a warehouse. Compaction handles "it does not fit right now", memory handles "will we remember next time". Both are lossy, so get anything important into readable files early, and start a new session with a hand-off doc when compaction starts to drift.
Companion skills:
long-session-check- sort context into drop / summarize / write to file, choose between compacting, rewinding and starting fresh, or review an agent's compaction and memory design.handoff-doc- goal, decisions, ruled-out approaches, current state, next step.
Plain-text checklist: checklists/long-session.md
Install:
mkdir -p ~/.agents/skills
cp -R ~/mcode-stack/stacks/ronny/skills/long-session-check ~/.agents/skills/
cp -R ~/mcode-stack/stacks/ronny/skills/handoff-doc ~/.agents/skills/