A second brain
that thinks alongside you.

Semantic search, a live knowledge graph, and vault editing for your Obsidian notes — wired straight into Claude and every other MCP client. Runs as one stdio process on your machine. Vault content never leaves it.

Get started View on GitHub

$npx -y obsidian-brain server

Find

Semantic search

Vector similarity over locally-embedded chunks, unified with SQLite FTS5 full-text. Ask in natural language; rank by meaning, not just keywords.

search tool

Map

Knowledge graph

Connection neighbourhoods, shortest paths between notes, Louvain-clustered themes, and PageRank over your backlink graph.

graph tools

Write

Vault editing

Create, append, patch-heading, patch-frontmatter, rename, link, delete. Every write re-indexes the affected file in milliseconds.

write tools

Extend

Companion plugin

An optional Obsidian plugin exposes live editor state and Dataview DQL query results — the two things the filesystem alone can't tell you.

plugin docs

Private

Local only

One stdio process on your machine. No API keys, no hosted endpoint, no remote URL. Your vault content never leaves.

architecture

Fast

Incremental index

SQLite with sqlite-vec and FTS5, incremental mtime sync plus a chokidar file watcher. Microsecond reads; writes land on disk immediately.

live updates

A second brain that thinks alongside you.