Mac Health MCP – ask Claude why your Mac is slow

Asks your Mac what's wrong and tells you in plain English.

The explanation comes first, then the numbers behind it.

A Model Context Protocol server that lets Claude Desktop, Claude Code and other MCP clients check your Mac's health: uptime, memory, disk, busy processes, Spotlight, heat, battery and startup items. Ask "Why is my Mac slow?" and Claude gets a ranked list of likely causes, each with a plain explanation, the number behind it and what you can do. Local, read-only, zero dependencies.

Built with Claude.

The same kind of conversation as text (made-up example values):

You:     Why is my Mac slow?

Claude:  I found 3 likely causes, most likely first:

         1. It has been a long time since the last restart (uptime 23 days).
            Apps and macOS slowly pile up memory and background work over time.
            Restart the Mac when it suits you.
         2. Memory is tight (memory pressure: warning, 4.2 GB swap).
            macOS is moving memory out to the disk, which is much slower.
            The apps using the most memory are ExampleBrowser (3.1 GB) and
            DemoApp (1.8 GB). Closing tabs or apps you don't need will help.
         3. One app is keeping the processor busy (DemoApp at 145 % CPU in both
            measurements). Quit it if you don't need it right now.

         Free disk space, Spotlight, heat, battery health and startup items
         look fine.

1. Download mac-health-x.y.z.mcpb from thelatest release on GitHub .
2. Double-click the file (or drag it into Claude Desktop, or use Settings → Extensions → Install Extension… ).
3. Click Install , then ask Claude:"Why is my Mac slow?"

Claude Desktop runs the extension with its own built-in Node.js, so nothing else needs to be installed.

Download or clone the repository to a permanent folder. No npm install is needed (there are no dependencies). Replace /path/to/mac-health-mcp below with the real folder.

git clone https://github.com/Swedishwizards/mac-health-mcp.git

Claude Desktop: open Settings → Developer → Edit Config (the file ~/Library/Application Support/Claude/claude_desktop_config.json) and add:

{
  "mcpServers": {
    "mac-health": {
      "command": "node",
      "args": ["/path/to/mac-health-mcp/server/index.js"]
    }
  }
}

Restart Claude Desktop afterwards. If Claude Desktop cannot find node, use the full path from which node (for example /opt/homebrew/bin/node or /usr/local/bin/node) as command.

Claude Code:

claude mcp add mac-health -- node /path/to/mac-health-mcp/server/index.js

Any other MCP client: run node /path/to/mac-health-mcp/server/index.js as a stdio server.

All tools are read-only and local. Every answer starts with a short plain-language summary, followed by the numbers as structured data. The built-in summaries and grades are in Swedish (Bra = good, Okej = OK, Behöver åtgärd = needs attention, Okänd = unknown); Claude answers you in your own language.

Answers "why is my Mac slow?" with a ranked list of likely causes, each with a plain explanation, the number behind it and what you can do.

Every command runs once and is shared between the checks. A check is only called "looks good" if it could actually be made; checks that could not run are listed as unknown. Causes are likely, not certain, and nothing is ever changed.

A health check of the whole Mac, each part graded, with advice when something is off:

If a command is missing, fails or times out, that part is reported as Okänd (unknown) instead of the whole tool failing.

• Local only. Everything runs on your Mac with built-in macOS tools (sysctl ,sw_vers ,vm_stat ,memory_pressure ,df ,du ,top ,ps ,pmset ,ioreg ). No network requests.

• No telemetry. Nothing is collected, stored or sent anywhere; the only output is the answer to your MCP client.

• Read-only. Never deletes, closes or changes anything. No admin password.startup_items only lists folder contents anddisk_report only reads sizes.

• Identifiers are filtered out. Only whitelisted values are parsed, and a final filter on every answer removes serial numbers, UUIDs, hardware IDs, MAC addresses, your user name, your computer name and home folder paths (shown as~ ) before anything is sent to Claude.

• Safe commands. Commands run without a shell, with absolute paths, a fixed locale and a timeout.

• macOS. The tools rely on built-in macOS commands; on other systems every tool answers that it only works on macOS.

• Node.js 18 or newer. With the .mcpb install (option A) Claude Desktop provides Node.js itself; for manual configuration (option B) Node.js 18+ must be installed.

• No npm install , no dependencies.

npm test         # runs on any OS (macOS and Linux in CI) with made-up command output from test/fixtures
npm run pack     # builds dist/mac-health-<version>.mcpb with the official packer (downloads it the first time)
npm start        # runs the MCP server over stdio

Quick manual check without a client:

printf '%s\n' \
  '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18"}}' \
  '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}' \
  | node server/index.js

Project layout:

server/index.js        MCP server (JSON-RPC over stdio), tool definitions, privacy filter on every answer
server/lib/collect.js  runs the read-only macOS commands (no shell, timeouts)
server/lib/parse.js    parses command output (whitelisted fields only)
server/lib/overview.js get_mac_overview: sections and grades
server/lib/diagnose.js diagnose_slowness: the eight checks
server/lib/reports.js  the other tools
server/lib/explain.js  plain-language names for macOS processes
server/lib/privacy.js  removes identifiers before anything leaves
test/                  tests with saved, made-up command output (fixtures) and a fake backend

CI runs the tests on macOS (main runner) and Ubuntu with Node 18 and 22, plus a stdio smoke test, and builds the .mcpb as a downloadable artifact. Nothing is published from CI.