Thebrain

io.github.yBookoff/thebrain · v0.3.0

MCP server for TheBrain 15: search by meaning, graph traversal and batch writes over the local API

Source code Set it up

Connect Runs on your machine

Terminal

claude mcp add thebrain -e THEBRAIN_API_KEY=<THEBRAIN_API_KEY> -e THEBRAIN_BASE_URL=<THEBRAIN_BASE_URL> -e THEBRAIN_DATA_DIR=<THEBRAIN_DATA_DIR> -e THEBRAIN_ALLOW_DESTRUCTIVE=<THEBRAIN_ALLOW_DESTRUCTIVE> -e THEBRAIN_EMBEDDING_MODEL=<THEBRAIN_EMBEDDING_MODEL> -e THEBRAIN_EMBEDDING_DTYPE=<THEBRAIN_EMBEDDING_DTYPE> -e THEBRAIN_TIMEOUT_MS=<THEBRAIN_TIMEOUT_MS> -- npx -y [email protected]

claude_desktop_config.json

{
  "mcpServers": {
    "thebrain": {
      "command": "npx",
      "args": [
        "-y",
        "[email protected]"
      ],
      "env": {
        "THEBRAIN_API_KEY": "<THEBRAIN_API_KEY>",
        "THEBRAIN_BASE_URL": "<THEBRAIN_BASE_URL>",
        "THEBRAIN_DATA_DIR": "<THEBRAIN_DATA_DIR>",
        "THEBRAIN_ALLOW_DESTRUCTIVE": "<THEBRAIN_ALLOW_DESTRUCTIVE>",
        "THEBRAIN_EMBEDDING_MODEL": "<THEBRAIN_EMBEDDING_MODEL>",
        "THEBRAIN_EMBEDDING_DTYPE": "<THEBRAIN_EMBEDDING_DTYPE>",
        "THEBRAIN_TIMEOUT_MS": "<THEBRAIN_TIMEOUT_MS>"
      }
    }
  }
}

~/.cursor/mcp.json

{
  "mcpServers": {
    "thebrain": {
      "command": "npx",
      "args": [
        "-y",
        "[email protected]"
      ],
      "env": {
        "THEBRAIN_API_KEY": "<THEBRAIN_API_KEY>",
        "THEBRAIN_BASE_URL": "<THEBRAIN_BASE_URL>",
        "THEBRAIN_DATA_DIR": "<THEBRAIN_DATA_DIR>",
        "THEBRAIN_ALLOW_DESTRUCTIVE": "<THEBRAIN_ALLOW_DESTRUCTIVE>",
        "THEBRAIN_EMBEDDING_MODEL": "<THEBRAIN_EMBEDDING_MODEL>",
        "THEBRAIN_EMBEDDING_DTYPE": "<THEBRAIN_EMBEDDING_DTYPE>",
        "THEBRAIN_TIMEOUT_MS": "<THEBRAIN_TIMEOUT_MS>"
      }
    }
  }
}

.vscode/mcp.json

{
  "servers": {
    "thebrain": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "[email protected]"
      ],
      "env": {
        "THEBRAIN_API_KEY": "<THEBRAIN_API_KEY>",
        "THEBRAIN_BASE_URL": "<THEBRAIN_BASE_URL>",
        "THEBRAIN_DATA_DIR": "<THEBRAIN_DATA_DIR>",
        "THEBRAIN_ALLOW_DESTRUCTIVE": "<THEBRAIN_ALLOW_DESTRUCTIVE>",
        "THEBRAIN_EMBEDDING_MODEL": "<THEBRAIN_EMBEDDING_MODEL>",
        "THEBRAIN_EMBEDDING_DTYPE": "<THEBRAIN_EMBEDDING_DTYPE>",
        "THEBRAIN_TIMEOUT_MS": "<THEBRAIN_TIMEOUT_MS>"
      }
    }
  }
}

Replace the values in angle brackets with your own. Keys stay on your machine; we never see them.

Tools

This server runs locally, so its tools are listed by your MCP client once it starts.

Environment variables

Name	Description
`THEBRAIN_API_KEY` Required, secret	Local API key from TheBrain: Settings > User > Local API Key
`THEBRAIN_BASE_URL` Optional	Address of the local API. Default http://localhost:11522, then http://localhost:8001 for older TheBrain builds
`THEBRAIN_DATA_DIR` Optional	Where semantic indexes are stored. Default ~/.thebrain-mcp
`THEBRAIN_ALLOW_DESTRUCTIVE` Optional	Set to 1 to allow deleting thoughts. Deletion still requires human confirmation. Default 0
`THEBRAIN_EMBEDDING_MODEL` Optional	Embedding model for semantic search. Default Xenova/multilingual-e5-small
`THEBRAIN_EMBEDDING_DTYPE` Optional	Weight precision: fp32, fp16, q8 or q4. Default q8
`THEBRAIN_TIMEOUT_MS` Optional	API request timeout in milliseconds. Default 30000

Details

Package	`[email protected]` (NPM, stdio)
First published	14 Oct 2026
Last updated	14 Oct 2026
Registry name	`io.github.yBookoff/thebrain`

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Live status

Local install

Installed and run on your own machine, so there is no public endpoint to check.

Pair it with live search

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