SilverBullet MCP server

silverbullet-mcp

A tiny MCP server that gives any MCP-capable agent read/write access to a SilverBullet space.

No dependencies — Python 3 stdlib only. It is a translator: it forwards MCP tool calls to SilverBullet's built-in /.fs HTTP API, which already supports read, write and delete. Nothing needs to be installed or patched inside SilverBullet.

It is small enough to read in one sitting, and it speaks both MCP transports that clients actually use: stdio (spawned by Claude Desktop, Cursor, and friends) and streamable HTTP (shared or remote access behind a reverse proxy).

Quick start

Run it as a server:

git clone https://github.com/wicahma/silverbullet-mcp.git
cd silverbullet-mcp
cp .env.example .env      # set MCP_TOKEN, and SB_URL if SilverBullet is elsewhere
set -a; . ./.env; set +a
python3 sb_mcp.py         # streamable HTTP on http://127.0.0.1:9339/mcp

Or let a client spawn it — no clone required, since it ships on npm:

SB_URL=http://127.0.0.1:8123 npx -y silverbullet-mcp --stdio

Tools

Paths are space-relative (Projects/Foo.md), restricted to .md, and .. segments are rejected.

Transports

Both come from the same code and expose the same six tools. MCPTOKEN only matters in HTTP mode; the SB variables describe the upstream space in both.

Client setup

Claude Desktop

Edit ~/Library/Application Support/Claude/claudedesktopconfig.json (macOS) or %APPDATA%\Claude\claudedesktopconfig.json (Windows):

{
  "mcpServers": {
    "silverbullet": {
      "command": "npx",
      "args": ["-y", "silverbullet-mcp", "--stdio"],
      "env": { "SB_URL": "http://127.0.0.1:8123" }
    }
  }
}

Cursor

Same body, in .cursor/mcp.json for one project or ~/.cursor/mcp.json globally.

Any client that speaks remote MCP

{
  "mcpServers": {
    "silverbullet": {
      "type": "http",
      "url": "https://your-host.example/mcp",
      "headers": { "Authorization": "Bearer <MCP_TOKEN>" }
    }
  }
}

Local, with no reverse proxy in front:

{
  "mcpServers": {
    "silverbullet": {
      "type": "http",
      "url": "http://127.0.0.1:9339/mcp",
      "headers": { "Authorization": "Bearer <MCP_TOKEN>" }
    }
  }
}

Note for remote clients: url must be, or must proxy to, this bridge — not SilverBullet itself. SilverBullet has no MCP endpoint of its own; that is what this project adds.

Configuration

All configuration is environment variables, so the same code runs for anyone.

Shortened. The full README is on GitHub.