brain2

Database-first personal knowledge management system powered by a local MCP server. All data lives in a single SQLite file. Claude accesses it via 29 MCP tools through Claude Desktop or Claude Code.

Replaces an earlier Obsidian vault-based system with structured storage, semantic search, and automated ingestion pipelines.

Features

• Unified knowledge store — meetings, emails, chats, notes, people, accounts, projects, todos, ideas, and resources in one database

• Knowledge graph — flexible edges between any entities (mentions, related_to, attended, about, etc.)

• Hybrid search — FTS5 full-text search + sqlite-vec vector similarity (384-dim, all-MiniLM-L6-v2)

• Watermark-based ingestion — incremental M365 email sync with dedup (Teams chat sync currently unavailable)

• Dreaming — connection building, person summaries, account health assessment, and theme discovery — runs at the end of each sync

• Daily digest — morning briefing with meetings (account context, open threads, heads-up) and overdue todos

Related MCP server: knowledgine

Requirements

• Node.js 20+

• Claude Desktop or Claude Code (for MCP integration)

• Microsoft 365 MCP (for email/chat ingestion)

Setup

npm install

Configure MCP

Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json) or Claude Code config (~/.claude/mcp.json):

{
  "mcpServers": {
    "brain2": {
      "command": "npx",
      "args": ["tsx", "/path/to/brain2/src/index.ts"],
      "env": {
        "BRAIN2_DB": "/path/to/brain2/data/brain2.db"
      }
    }
  }
}

Import from Obsidian vault (optional)

npx tsx src/index.ts --import-vault ~/path/to/obsidian-vault

Parses frontmatter, tables, and imports all entity types (meetings, emails, chats, people, accounts, projects, todos, resources).

Usage

npx tsx src/index.ts          # Start MCP server (stdio)
npm test                      # Run tests
npx tsc --noEmit              # Type-check

Once the server is running, Claude can use all 26 tools and 4 skill prompts through natural conversation:

• "What's happening with the Dell account?" — searches items, gets account profile and contacts

• "Process my emails" — runs the email ingestion pipeline

• "Who have I met with most this month?" — queries the knowledge graph

• "Add a todo to follow up with Sarah by Friday" — creates a todo with due date

Architecture

data/brain2.db               SQLite + sqlite-vec + FTS5
data/models/                 Cached embedding model (all-MiniLM-L6-v2)

src/
  index.ts                   Entry point (stdio MCP transport + vault migration CLI)
  server.ts                  MCP server setup and tool registration
  db/
    connection.ts            SQLite connection with sqlite-vec extension
    schema.ts                Table definitions and migrations
  tools/
    ingest.ts                Ingest meetings, emails, chats, notes (5 tools)
    entities.ts              Upsert people/accounts/projects, manage todos (6 tools)
    query.ts                 Get/list items, people, accounts (6 tools)
    search.ts                Hybrid FTS5 + vector search (1 tool)
    graph.ts                 Edges and knowledge graph traversal (3 tools)
    synthesis.ts             Save/retrieve dreaming syntheses (2 tools)
    watermark.ts             Ingestion watermark tracking (3 tools)
    stats.ts                 Database stats and portfolio view (2 tools)
  embeddings/                Local embedding generation via @xenova/transformers
  search/                    Hybrid search ranking logic
  migration/                 Obsidian vault import
  utils/                     Hashing, ID generation

  prompts.ts                 Registers skills as MCP prompts for Claude Desktop

skills/                      Skill prompts (MCP prompts + Claude Code skills)
  brain-sync.md              Sync M365 → brain2 (email + chat) + dream + lint
  brain-day.md               Daily prep brief
  brain-note.md              File user notes to calendar meetings
  brain-extract.md           Extract reusable knowledge from work sessions

Skills

Skills are available as MCP prompts in Claude Desktop (via the / menu) and as Claude Code skills (via ~/.claude/skills/). Both read from the same skills/*.md files.

Data Model

Core entities

• items — unified table for meetings, emails, chats, notes

• people — one row per person with contact info (name, title, company, email, phone)

• accounts — customer accounts with health, platform, segment, ARR

• projects — active work with status tracking

• todos — action items with priority, due date, source item, assignee

• ideas / resources — captured ideas and reference material

Relationships

• item_people — who attended/participated in which item

• account_contacts — people linked to accounts with roles (ae, csa, se, tam, etc.)

• edges — generic typed relationships between any entities

• tags — flexible tagging on any entity

Search

• FTS5 index on item content and titles

• sqlite-vec 384-dimensional vectors for semantic similarity

• Hybrid ranking combines both signals

License

Private.