macnet

MacNet

A small macOS menu bar app that tells you whether your internet works, how fast it answers, and — when it does not — where the problem is: your Wi‑Fi/router, DNS, or your provider.

Features

• Ping in the menu bar — a dot from green to red plus milliseconds (or just the dot, or colored numbers).
• Diagnosis — every check pings the target and your router and times a DNS lookup, then tells you: All good, Local network problem, DNS problem, Internet provider problem, Slow local network or No network.
• Addresses at a glance — local IP, external IP, router IP and DNS servers, each with a copy button.
• Adaptive interval — every 5 s by default: 2.5 s while the link is unstable, stretching to 25 s while it is stable; slower on battery and on metered or Low Data networks. Uses well under 1% CPU.
• History, kept forever — every minute is logged to a local SQLite database. Browse by day, week, month, year or all time, search outages (provider, 2026-10-14, >5m), and export CSV.
• Outage journal — confirmed drops with their cause, uptime per day and downtime by cause.
• Network tools — Wi‑Fi signal and link rate, VPN detection, public IP, and an on-demand speed test (Apple's networkQuality).
• Notifications when the internet drops and comes back (debounced, no spam on flapping).
• Pause for 15 minutes, an hour, or until resumed.
• Agent access (MCP) — optional, read-only access for AI agents such as Claude Code. See below.

Home	History

Network	Settings

Requirements

• macOS 14 Sonoma or later
• Xcode 16 or later (Swift 6). Command Line Tools alone are not enough to run the tests.

Build and run

git clone https://github.com/SergKlein/macnet.git
cd macnet
scripts/bundle.sh
open build/MacNet.app

scripts/bundle.sh builds a release binary, wraps it into build/MacNet.app and signs it ad hoc. Move the app to /Applications if you want Launch at login.

Run the tests:

DEVELOPER_DIR=/Applications/Xcode.app/Contents/Developer swift test

Permissions macOS will ask for

Permission	Why
Local Network	To ping your router. Without it macOS blocks LAN access and the router shows as unreachable.
Notifications	Optional, for "Internet connection lost / restored".
Location	Optional, only to show your Wi‑Fi network name (macOS hides it otherwise). Your location is never stored or sent.

Privacy

MacNet talks to the network only to do its job:

• ICMP ping to your target (default 1.1.1.1) and your router;
• http://captive.apple.com/hotspot-detect.html every ~10 s to tell "no internet" from "target not responding";
• a DNS lookup of a random *.apple.com name to time your resolver;
• https://1.1.1.1/cdn-cgi/trace for your external IP — only when you open the menu (at most every 5 minutes) or press Refresh;
• Apple's networkQuality — only when you press Run speed test.

History stays on your Mac in ~/Library/Application Support/MacNet/macnet.sqlite. Nothing is uploaded.

Agent access (MCP)

MacNet can expose its state to AI agents over MCP (Streamable HTTP with SSE). It is off by default and read-only.

1. Open Settings… → Agent access and switch it on.

2. Press Copy Claude Code command and run it, for example:

   claude mcp add --transport http macnet http://127.0.0.1:7341/mcp --header "Authorization: Bearer <token>"
   

Tools: get_status (including exactly what the menu bar shows), get_history, get_stats, list_targets, get_events, get_diagnosis, get_outages, get_network_details, get_history_stats, wait_for_state, wait_for_event. Resources macnet://status, macnet://history and macnet://events support subscriptions.

wait_for_state and wait_for_event let an agent verify behavior, e.g. "turn Wi‑Fi off and wait until MacNet reports offline".

Security: the server binds to 127.0.0.1 only, requires the bearer token, rejects non-loopback Origin headers, caps connections and request sizes, and never changes settings or runs a lookup or speed test on an agent's behalf.

Smoke test from a terminal:

scripts/mcp-smoke.sh <token>

Architecture

Swift Package with four modules:

Module	Contents
MacNetCore	Domain logic (state, diagnosis, jitter, outages, history roll-ups), ports (protocols for every I/O), the MonitorCoordinator actor, view models and the MCP protocol layer. Imports only Foundation and Observation.
MacNetServer	Loopback MCP HTTP server on Network.framework.
MacNetStorage	SQLite storage (system libsqlite3).
MacNet	The app: adapters (/sbin/ping, NWPathMonitor, CoreWLAN, SystemConfiguration, UserNotifications, SMAppService), SwiftUI views and the composition root.

No third-party dependencies. Swift 6 strict concurrency, zero warnings, swift format lint --strict clean.

License

Apache License 2.0 © 2026 Sergii Brul