Mnemo (Mnemosyne)

Read-only block extractor + multi-session indexer for Claude Code conversations. Walks JSONL transcripts under ~/AppData/Local/Temp/claude/, extracts structured blocks (architecture diagrams, decisions, todos, open questions), and serves them via a SQLite store + MCP server + small pywebview viewer.

Status: v0.5 — multi-session indexer with per-session offsets. 88 tests green.

What it surfaces

Mnemo parses each Claude Code session's JSONL transcript and finds delimited blocks like :

$ARCHITECTURE
graph TD
  A --> B
$END

$DECISION
Use Mermaid IIFE bundle (offline cybersec posture).
$END

$TODO
- [x] Ship V4 layout
- [ ] Ship V5 dashboard
$END

These get extracted, deduplicated by content hash, indexed by (project, source, captured_at), and made queryable via the BlockStore.

Run

CLI viewer

python -m mnemo

Opens a pywebview window with 3 modes — Visualizer, Editor, Diff — over the indexed blocks. Live scan refreshes every 5s.

MCP server

mnemo-mcp

Exposes BlockStore over stdio MCP for the Vinom Cockpit aggregator and any Claude Desktop client. Default DB: ~/.mnemo/mnemo.db.

Programmatic

from mnemo.store import BlockStore
store = BlockStore()  # opens ~/.mnemo/mnemo.db
blocks = store.list_blocks(project="vinom", source="session:<id>", limit=50)

Storage

SQLite at ~/.mnemo/mnemo.db. Single blocks table keyed by content hash with a composite index idx_blocks_project_source_captured(project, source, captured_at DESC) so the cockpit aggregator's (project, source) lookups are direct seeks instead of full scans (~3 ms at 10K blocks).

Multi-session indexing : the scanner tracks per-session JSONL byte offsets in a sessions table so re-runs only parse new appends.

Used by

• Vinom Cockpit aggregator — reads mnemo.db to populate Architecture
  • Decisions + Todos columns of the V4 GUI (5s scan, <10s end-to-end latency for new blocks).
• mnemo-mcp server in Claude Desktop / cursors / any MCP host.

Test

.venv\Scripts\python.exe -m pytest tests/ -q
# → 88 passed

Spec

vinom/docs/superpowers/specs/2026-05-01-mnemo-design.md — original design, plus follow-ups for the v0.5 multi-session pivot in the same folder.

Why "Mnemosyne"

In the FORGE-suite mythology, Mnemosyne is the muse of memory — keeps the durable thread of every conversation Claude has had on this machine. Sister to Vinom Cockpit (the workspace) and FORGE (the architecture builder).

License

Apache 2.0