If you have ever had AI hallucinate and make things up (and gaslight you, even): it's because summaries do not preserve nuance. Each /compact cycle summarises and compresses. Decisions lose their rationale. Lessons lose their context. By Monday, you're re-explaining choices you made on Thursday. That's context rot. PMM fixes that. Every session, Claude loads what it already knows, then adds to it. Markdown files, git-backed. No database, no setup. Decisions tracked with rationale: not just what but. git log as your memory audit trail. Memory that compounds, not rots.