Local Brain

MCP server that gives Claude read-only access to your Obsidian vault — your personal knowledge base.

Write your skills, patterns, conventions, and preferences in Obsidian. Brain makes Claude consult them before every task, so it works the way you want.

How it works

You write knowledge in Obsidian
        ↓
Brain exposes it via MCP (read-only)
        ↓
Claude searches your vault FIRST before any task
        ↓
Your knowledge guides Claude's work

The workflow is strict:

1. Claude always searches your vault first
2. If it finds what it needs → applies it exactly
3. If it finds partial info → uses it as base + complements
4. Only if nothing is found → falls back to its own knowledge

Install

Download from releases

Go to Releases and download the binary for your platform:

Platform	File
macOS Apple Silicon	brain-macos-aarch64.tar.gz
macOS Intel	brain-macos-x86_64.tar.gz
Linux x86_64	brain-linux-x86_64.tar.gz
Linux ARM64	brain-linux-aarch64.tar.gz
Windows x86_64	brain-windows-x86_64.zip

# Extract (macOS/Linux)
tar xzf brain-<platform>.tar.gz
chmod +x brain

# Move to a permanent location
mv brain /usr/local/bin/

Build from source

git clone https://github.com/your-user/local-brain.git
cd local-brain
cargo build --release
# Binary at ./target/release/brain

Register with Claude

Claude Code

claude mcp add brain -- brain "YourVaultName"

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "brain": {
      "command": "brain",
      "args": ["YourVaultName"]
    }
  }
}

Requirements

• Obsidian with the CLI enabled
• The obsidian command available in your PATH

Tools

Tool	Description
read_file	Read a note by name or path
read_files	Read multiple notes at once
list_files	List files in the vault or a folder
list_folders	List folder structure
search	Search text across the vault
search_with_context	Search with matching lines
tag_info	Get info about a specific tag
list_tags	List all tags
list_properties	List frontmatter properties
read_property	Read a frontmatter value
list_links	Outgoing links from a note
list_backlinks	What notes reference a note
list_templates	List available templates
read_template	Read a template
outline	Show headings structure of a note

All tools are read-only. Brain never modifies your vault.

Vault organization tips

How you organize your Obsidian vault is up to you. Some ideas:

• Use tags to categorize knowledge (e.g. #pattern, #skill, #convention)
• Use folders for domains (e.g. rust/, frontend/, devops/)
• Use frontmatter properties for metadata (e.g. type: skill, language: rust)
• Use links to connect related knowledge

The more structured your vault, the better Claude can find what it needs.

License

MIT