Mnemo

Persistent memory for Claude Code. Your AI never starts from scratch again.

Mnemo gives Claude Code a brain that survives across sessions. It captures decisions, conventions, and preferences — and recalls them by meaning, on demand, with sub-100ms semantic search.

Install

# install the CLI
npm install -g @mnemo-mcp/cli

# install Mnemo into Claude Code (skill + MCP server)
mnemo init

# (optional) also wire auto-capture hooks
mnemo init --with-hooks

# verify
mnemo doctor

After mnemo init, restart Claude Code. The /mnemo skill and the mnemo_* MCP tools are now available — Claude will use them automatically when relevant.

Use it from the terminal too

mnemo remember "our API auth uses OAuth2 with refresh tokens every 30min"
mnemo remember --global "I prefer pnpm over npm"
mnemo recall "what's our auth pattern?"
mnemo list
mnemo stats
mnemo forget <id>
mnemo export --out memories.json
mnemo import memories.json

What Mnemo solves

Claude Code forgets everything when the session ends. CLAUDE.md partially helps — it's a static blob loaded on every turn — but it grows unwieldy fast and can't answer "do we have a precedent for X?"

Mnemo gives you semantic, on-demand memory:

| | CLAUDE.md | Mnemo | |---|---|---| | Capacity | A handful of paragraphs before token cost hurts | Tens of thousands of memories | | Retrieval | Always loaded, every turn | On demand, by meaning | | Updates | You edit a file by hand | Captured automatically or via /teach | | Cross-project | Per-project only | Project + global tiers | | Forgetting | Manually delete lines | mnemo forget <id> or /forget |

How it works

Claude Code session
  ├── /mnemo skill              ← teaches Claude when to call the tools
  ├── @mnemo-mcp/server server          ← exposes recall/remember/forget/list/stats
  └── @mnemo-mcp/cli hooks           ← session-start, pre-task, post-edit auto-wiring
              │
              ▼
       @mnemo-mcp/core
       ├── ONNX all-MiniLM-L6-v2  (384-dim embeddings, ~25MB, lazy)
       ├── HNSW vector index      (sub-100ms recall at 50k memories)
       └── sql.js (WASM SQLite)   (~/.mnemo/memory.db)

Everything is local-first. No daemon. No cloud account. No telemetry.

Auto-capture rules

By default the post-edit hook captures any change to:

• CLAUDE.md, AGENTS.md, GEMINI.md
• *.adr.md
• docs/decisions/**
• docs/adr/**

Anything you write to those files becomes a project memory automatically. Disable with mnemo init (no --with-hooks).

Recall scoring

score = 0.7 × cosine_similarity + 0.2 × recency + 0.1 × access_boost

Recency decays with a 30-day half-life. Access boost saturates at 20 reads.

Layout

@mnemo-mcp/core   — pure TS memory engine
@mnemo-mcp/server    — MCP server (drop into Claude Code)
@mnemo-mcp/cli    — terminal commands + hook handlers + init

Roadmap

• ✅ v0.1 — core engine + CLI
• ✅ v0.2 — MCP server (5 tools)
• ✅ v0.3 — hooks (session-start, pre-task, post-edit)
• ✅ v0.4 — /mnemo skill
• ✅ v1.0 — mnemo init, beefier doctor, CI, polish
• ⏳ v1.1 — team mode (git-synced shared memory)
• ⏳ v2.0 — opt-in hosted sync, web UI

Development

npm install
npm test                                    # fast (44 tests, hash embedder)
MNEMO_TEST_ONNX=1 MNEMO_E2E=1 npm test     # full incl. real ONNX (~5s)
npm run build
npm run lint

License

MIT — see LICENSE.