Install the MCP Server

Prerequisites

• The Nullstone CLI installed and on your PATH.
• A Nullstone account with an API key (see Authentication).

1. Install the server binary

Option A — pre-built release

Download the binary for your platform from the releases page:

Platform	Asset
Linux x64	nullstone-mcp-linux-amd64
macOS Intel	nullstone-mcp-darwin-amd64
macOS Apple Silicon	nullstone-mcp-darwin-arm64
Windows x64	nullstone-mcp-windows-amd64.exe

Place it somewhere on your PATH (e.g. /usr/local/bin/nullstone-mcp) and make it executable.

Option B — build from source

Requires Go 1.22+.

git clone https://github.com/nullstone-io/mcp-server.git
cd mcp-server
go build -o nullstone-mcp .

2. Register with your MCP client

Claude Code

Add to your Claude Code MCP configuration:

{
  "mcpServers": {
    "nullstone": {
      "command": "/absolute/path/to/nullstone-mcp"
    }
  }
}

If you've already run nullstone configure, no additional env vars are needed — the server reads your profile.

Claude Desktop

Add to your Claude Desktop config file.

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %AppData%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "nullstone": {
      "command": "/absolute/path/to/nullstone-mcp"
    }
  }
}

Restart Claude Desktop after editing.

Cursor (and other MCP clients)

Any MCP-compatible client that supports stdio transport works. Point it at the binary; provide auth via profile or env vars as described in Authentication.

3. Verify

In your client, ask the agent to run the nullstone_profile tool. You should see a JSON envelope with your user, org, and API endpoint. If not, see Troubleshooting.

Troubleshooting

"nullstone not found in PATH" — the server shells out to the nullstone CLI. Install it and confirm which nullstone works in the same shell the MCP runs in.

401 / unauthorized — your API key is missing or wrong. See Authentication.

Tool list is empty or partial — the server ran nullstone --help and failed to parse output. Update both the CLI and the MCP binary to their latest releases.

Agent calls the wrong org — verify nullstone_profile returns the org you expect. If it doesn't, run nullstone set-org <org> in the same environment the MCP runs in, or set NULLSTONE_ORG in the MCP's env block.