Big Brain runs on your own machine — the client starts it, so there is no endpoint to ping. 58 installs a week from npm. Last commit 15 Oct 2026.
Plain-markdown second brain for you and your AI: notes, projects, tasks, search, links.
What the code does
We read the source, 4 d ago · rules 995398eba69f
What this server is able to do. For an MCP server this is often the job itself — a terminal server runs commands because that is what it is for. Listed so you know what you are plugging in, not as an accusation.
const child = spawn(process.execPath, [serverPath, ...args], { stdio: "inherit" });
return !fs.existsSync(path.join(this.vaultDir, notePath));
Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.
This code can reach further than it looks
We found places where it runs commands, builds paths or queries from values it is given. None of that is a flaw by itself — it becomes one when the code changes, and code changes quietly between releases. We re-read it on every one.
Connect this server
This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.
claude mcp add big-brain -e 'BIG_BRAIN_VAULT=<BIG_BRAIN_VAULT>' -- npx -y @jzhao234/big-brain{
"mcpServers": {
"big-brain": {
"command": "npx",
"args": [
"-y",
"@jzhao234/big-brain"
],
"env": {
"BIG_BRAIN_VAULT": "<BIG_BRAIN_VAULT>"
}
}
}
}[mcp_servers.big-brain]
command = "npx"
args = ["-y", "@jzhao234/big-brain"]
env = { BIG_BRAIN_VAULT = "<BIG_BRAIN_VAULT>" }{
"mcpServers": {
"big-brain": {
"command": "npx",
"args": [
"-y",
"@jzhao234/big-brain"
],
"env": {
"BIG_BRAIN_VAULT": "<BIG_BRAIN_VAULT>"
}
}
}
}{
"servers": {
"big-brain": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@jzhao234/big-brain"
],
"env": {
"BIG_BRAIN_VAULT": "<BIG_BRAIN_VAULT>"
}
}
}
}Put your own value in place of
<BIG_BRAIN_VAULT> (Folder of your vault (an existing Obsidian vault works, or run `big-brain init` first)).
The author’s registry entry marks it as required.
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Big Brain — questions
Answers built from our own checks of this server.