This note was created on 2026-06-28 as a session-resume cache convention, then withdrawn in the same session after recognising the preconditions weren't met. The core problem: there is no reliable trigger for writing this note at session end (context exhaustion, tab close, or topic change all end sessions without any signal). A single mutable note is also wrong for a multi-agent system — last writer wins, and stale content is worse than no content.
The right implementation is the append-only log subsystem (see proposals/log-structure), where session summaries are logentry blocks written opportunistically. Until that exists, session context is reconstructed from MEMORY + CONTENTS as before. Note: a notes:delete MCP tool does exist — earlier claims to the contrary in this session were wrong.
Do not implement this pattern or reference this note until the log subsystem is built and the write-trigger problem is solved.