**memsearch** (Milvus Lite, embedded), and **semantic/knowledge** ("how do we…") handled by the
existing **`~/Documents/SecondBrain` Obsidian vault** as the single source of truth. Notes keep
`summary` + six flat, parallel namespaced facets (`type/`/`client/`/`project/`/`domain/`/`tool/`/`convention/`) plus `scope/` as metadata; hierarchy and relationships are expressed via hub notes (`type/hub`), wikilinks, and Graphify graph edges — not nested tag paths. The vault is queried via a **Graphify knowledge graph** (local Ollama SLM for doc extraction, free
**Decisions locked (2026-06-04):** Six-facet tag taxonomy + `scope/` (ADR-011); reuse `~/Documents/SecondBrain` vault rather than creating a new one (ADR-012); build-first / migrate-incrementally — build full system against a fixture set first, defer bulk vault migration to last, onboard projects one at a time (ADR-013).
**Empirical finding locked (2026-06-05):** Graphify is a structure extractor, not a topic clusterer — no emergent hub nodes appear even at `--mode deep`; hub notes + wikilinks must be author-provided during migration (not deferred). Migration scaffolding is now a first-class deliverable. Open question: do facet tags create graph edges? (ADR-014; findings: `docs/memory-system/07-graph-connectivity-findings.md`).
**Implementation status (2026-06-09):** The global Claude Code plugin is live (`~/.claude/plugins/memory/`). Steps 1, 2a, 2b, 3, and 6 of the build plan are complete (including the `memory-project` skill, previously TODO under Step 6/Part D). Step 1 completed 2026-06-09: vault-conventions.md exists, all 6 fixture notes seeded, and 14 Graphify handbook + memory-system design notes migrated to the vault as migration scaffolding. Steps 4 (memsearch) and 5 (sync) remain. See `docs/memory-system/04-build-plan.md` for full step status.
- Vault conventions: `~/Documents/SecondBrain/vault-conventions.md` — frontmatter contract + tag taxonomy (canonical name decided 2026-06-09; formerly referred to as CONVENTIONS.md)
- **Keep this file current:** When a build step completes, (a) mark it done in `docs/memory-system/04-build-plan.md`, (b) add or update a component pointer in the Implemented Components section above, and (c) update the current design paragraph if the design changed. This file is the AI's orientation entry point — accuracy matters more than brevity.