mac-control-mcp

mac-control-mcp

Native Swift MCP server for full macOS automation. 153 tools in one signed .app bundle — no Python, no Node runtime, no Electron. Full list with parameters: docs/TOOLS.md.

Gives any MCP-compatible client (Claude Desktop, Claude Code, Cursor, etc.) the ability to:

• Read and mutate the Accessibility tree of any running app
• Drive Safari and Chrome (tabs, navigation, JS eval)
• Capture the screen, a display, or a specific window (ScreenCaptureKit)
• OCR what's on screen
• Click, type, scroll, drag, send key events
• Control windows (move / resize / fullscreen / minimize / main)
• Manage the clipboard
• Launch / activate / quit apps
• Search Spotlight's index (NSMetadataQuery) and launch results
• Toggle dark mode, volume, list displays, inspect menus

Install

Requires macOS 14.0+. Four options, in order of simplicity:

1. One-click install (Claude Desktop, recommended)

The server is published as an MCP Bundle — a zip with a manifest.json that Claude Desktop reads directly:

1. Download mac-control-mcp-v<version>.mcpb from the latest release.
2. Double-click the .mcpb file. Claude Desktop opens an install dialog.
3. Click Install. The server is registered under the name mac-control-mcp and available immediately in new chats.
4. First tool call triggers the macOS TCC consent prompts (Screen Recording, Accessibility, Apple Events). Grant all three once — the bundle is Developer-ID signed and notarized, so grants persist across updates.

It's also listed on the official MCP Registry as io.github.AdelElo13/mac-control-mcp, so any MCP client that supports the registry will find it by searching for "mac-control".

2. Install via npm / npx

For clients that are configured with a command line rather than a file path. The npm package mac-control-mcp is a thin launcher: it has no runtime dependencies, and on install it downloads the notarized MacControlMCP.app for that exact version from this repo's GitHub release, verifies it against the published .sha256, refuses any archive entry that escapes the install directory, and re-checks the bundle with codesign --verify --deep --strict, spctl --assess --type execute and a pinned Team ID (A3W973JZ49). The first run therefore pulls ~3 MB; later runs are local.

Claude Desktop — ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "mac-control-mcp": {
      "command": "npx",
      "args": ["-y", "mac-control-mcp"]
    }
  }
}

Claude Code:

claude mcp add mac-control-mcp -- npx -y mac-control-mcp

Cursor — ~/.cursor/mcp.json:

{
  "mcpServers": {
    "mac-control-mcp": {
      "command": "npx",
      "args": ["-y", "mac-control-mcp"]
    }
  }
}

ChatGPT (developer mode, local MCP connector) — mcp.json:

{
  "mcpServers": {
    "mac-control-mcp": {
      "command": "npx",
      "args": ["-y", "mac-control-mcp"],
      "transport": "stdio"
    }
  }
}

Two flags are handled by the launcher itself instead of being forwarded to the binary:

npx -y mac-control-mcp --version    # version of the bundled .app
npx -y mac-control-mcp --app-path   # path to MacControlMCP.app

--app-path is what you need when granting macOS permissions by hand. Note that TCC grants go to the MCP host application that launches this process (Claude Desktop, Cursor, your terminal), not to npx or to the script — run the permissions_status tool once from your client to see which grants are missing and which app they belong to.

MAC_CONTROL_MCP_SKIP_DOWNLOAD=1 skips the download (CI, sandboxed builds); HTTPS_PROXY and NO_PROXY are honoured.

3. Download the prebuilt app

If you don't use Claude Desktop or want manual control:

1. Download MacControlMCP-v<version>-macos-universal.tar.gz from the latest release.
2. Extract and move MacControlMCP.app to ~/Applications/.
3. Point your MCP client at the binary inside:

{
  "mcpServers": {
    "mac-control-mcp": {
      "type": "stdio",
      "command": "/Users/you/Applications/MacControlMCP.app/Contents/MacOS/MacControlMCP"
    }
  }
}

Add that block to ~/Library/Application Support/Claude/claude_desktop_config.json (Claude Desktop) or ~/.claude.json → mcpServers (Claude Code).

Verify the download with the published SHA-256:

shasum -a 256 MacControlMCP-v<version>-macos-universal.tar.gz
# should match MacControlMCP-v<version>-macos-universal.sha256 on the release

4. Build from source

For contributors or if you want to tweak the code. Requires Swift 6 / Xcode 16+:

git clone https://github.com/AdelElo13/mac-control-mcp.git
cd mac-control-mcp
./scripts/build-bundle.sh

Produces ~/Applications/MacControlMCP.app/Contents/MacOS/MacControlMCP. Without a Developer ID cert in your keychain it'll fall back to ad-hoc signing (works for local use, TCC grants reset on every rebuild).

To re-sign + re-notarise an existing Apple Developer account:

# one-time: store notary credentials in keychain
xcrun notarytool store-credentials "mac-control-mcp" \
    --apple-id "you@example.com" --team-id "XXXXXXXXXX"

# subsequent builds:
NOTARIZE_PROFILE=mac-control-mcp ./scripts/build-bundle.sh

Tool surface

Selected categories — this table is a curated subset, not the full list. For the complete, auto-generated tool reference (every tool, its description, and its required/optional parameters, regenerated straight from the tool registry so it can't drift), see docs/TOOLS.md.

Category	Tools
Permissions	permissions_status, request_permissions
Accessibility	find_element(s), query_elements, list_elements, get_ui_tree, ax_tree_augmented, get_element_attributes, set_element_attribute, read_value, perform_element_action, wait_for_element, scroll_to_element
App lifecycle	list_apps, launch_app, activate_app, quit_app, force_quit_app, wait_for_app, focused_app
Windows	list_windows, focus_window, move_window, resize_window, set_window_state, wait_for_window, move_window_to_display
Input	click, mouse_event, drag_and_drop, scroll, type_text, press_key, press_key_sequence, key_down, key_up, convert_coordinates
Menus	click_menu_path, list_menu_paths, list_menu_titles
Browser	browser_list_tabs, browser_get_active_tab, browser_navigate, browser_new_tab, browser_close_tab, browser_eval_js, browser_dom_tree, browser_visible_text, browser_iframes
Screen	capture_screen, capture_screen_v2, capture_window, capture_display, ocr_screen
Clipboard	clipboard_read, clipboard_write, clipboard_clear
Spotlight	spotlight_search, spotlight_open_result
System	set_volume, set_dark_mode, list_displays
File dialogs	file_dialog_set_path, file_dialog_select_item, file_dialog_confirm, file_dialog_cancel, wait_for_file_dialog
Apple apps	mail_send, imessage_send, imessage_list_recent, calendar_create_event, calendar_list_events, reminders_create, reminders_list, contacts_search
Voice & recording	speech_to_text, text_to_speech, audio_record, record_screen
Undo	undo_last_action, undo_peek

153 tools total — see [docs/TOOLS.md](docs/TOOLS.md) for the complete, generated list.

Which tool when

Several tools overlap in purpose. Based on their actual implementations:

Screen capture — capture_screen vs capture_screen_v2 vs capture_window vs capture_display

• capture_screen — main display (or a rectangular region within it) to a PNG file, returns the file path + width/height. Simple, synchronous, no size limits applied.
• capture_screen_v2 — main display only, but stores the PNG as a content-addressed artifact under ~/.mac-control-mcp/artifacts/<sha256>.png and returns {content_ref, bytes, sha256}. Defaults to inline=false and downscales to max_dimension/max_bytes (4000px / 4MB by default) specifically to avoid blowing up an MCP client's context window with a huge inline image (referenced in its own description as a fix for claude-code issues #13383/#45785). Prefer this one when the image is going back through an LLM context rather than straight to disk.
• capture_window — screenshots one specific window by PID (optionally filtered by title_contains), not the whole display.
• capture_display — screenshots one specific physical display by its index from list_displays, for multi-monitor setups.

Accessibility tree / element lookup — find_element vs find_elements vs query_elements vs list_elements vs get_ui_tree vs ax_tree_augmented

• list_elements — lists actionable elements for a PID (a flat, practical "what can I click" view).
• find_element — returns the first element matching a role/title filter for a PID.
• find_elements — same matching as find_element, but returns all matches, not just the first.
• query_elements — regex search over role/title/value (falls back to case-insensitive substring on invalid regex); use when a plain role/title filter isn't precise enough.
• get_ui_tree — walks the full accessibility tree of a process, including containers, and assigns stable element IDs for follow-up calls. Heavier than list_elements/find_element(s), but the only one that gives you structure/hierarchy.
• ax_tree_augmented — like get_ui_tree, but does one OCR pass and geometrically joins OCR-derived labels onto AX nodes that have no native label. Use it specifically for Electron/Chromium/Canvas apps where the native AX tree is sparse and unlabeled; it's the expensive option (an OCR pass), so reach for get_ui_tree first and fall back to this when nodes come back unlabeled.

Security model

• Tools that write files (capture_*, ocr_screen) validate output_path via a strict allow-list — only the user-scoped temp dir (NSTemporaryDirectory()) and ~/Desktop, ~/Documents, ~/Downloads, ~/Pictures are accepted. Symlinks at the target path are rejected to prevent redirection. /tmp is deliberately excluded because it's shared across users and opens a TOCTOU window.
• AppleScript string interpolation for browser_eval_js wraps user code in (0, eval)(…) via JSON.stringify, so quotes/newlines/unicode can't break out of the wrapper.
• No network calls. Everything is local system integration.
• Password fields are off limits in code, not by instruction. A field with role or subrole AXSecureTextField never returns its value or length, and every write route is refused with reason: secure_field: element writes, text_* edits, act, untargeted type_text, and text keys or Cmd+V via press_key, press_key_sequence and key_down while such a field has focus. While such a field has focus, menu-bar and context-menu items (Paste, Start Dictation, Emoji & Symbols) cannot be pressed either; pop-up and combo-box option menus stay usable. Navigation keys (Tab, Return, Escape, arrows) still work, so the agent can hand the field to the user. browser_eval_js runs arbitrary page JavaScript and is not covered by this guard.

Status (verified in the current release)

Scope	State
Unit / integration test suite	swift test, all green locally and on CI (macos-15) — see ci.yml
Live tool probe	A subset of tools exercised end-to-end via real MCP stdio against the running binary, all pass
Destructive tools (volume, dark mode, force_quit_app, drag_and_drop, file_dialog_*)	Verified live in a reversible way
Code signing	Developer ID Application (A3W973JZ49) with hardened runtime
Apple notarization	Accepted by Apple Notary Service, ticket stapled, spctl reports source=Notarized Developer ID
Gatekeeper flow	Extracted + launched with the com.apple.quarantine xattr set; no right-click-open needed
MCP Registry	Published as io.github.AdelElo13/mac-control-mcp (see server.json for the current version) — distributed as an .mcpb bundle for one-click install
Architectures	Universal binary (arm64 + x86_64). Intel slice compiles cleanly but has not been runtime-verified on actual Intel hardware
move_window_to_display	Skipped — requires a 2+ display setup

If you run into an untested path, please open an issue with the reproduction — happy to fix fast.

Caveats

• Cross-origin iframes block browser_eval_js — same-origin policy, not a limitation of the tool. Use AX coords or synthetic CGEvents for content inside embedded iframes from other origins.
• First-run TCC prompts are unavoidable. macOS requires the user to grant Screen Recording, Accessibility and Apple Events the first time. The usage-description strings in Info.plist make the consent dialogs show up with a clear reason, but you still need to click Allow in System Settings once.

Development

# Run the test suite
swift test

# Build without packaging
swift build -c release

# Live probe the running binary via MCP stdio
python3 scripts/mcp-sweep.py  # if included

License

MIT — see LICENSE.

Contributing

Issues and pull requests welcome. Adversarial reviews especially — prior releases went through 11 rounds of external review before shipping.