DSH for Mac

An unofficial native macOS app for DeepSeek Harness (dsh).

It runs the harness's own web UI inside a native window, so the interface is exactly the official one — same code, same features, same updates — while the app gives it what a browser tab cannot: a Dock icon, a real menu bar, window state that survives relaunches, and a dsh server whose whole lifecycle is owned by the app.

Not affiliated with or endorsed by DeepSeek. "DeepSeek" and "DeepSeek Harness" are trademarks of their respective owners.

What it does

• Starts dsh --profile web --no-open bound to 127.0.0.1 and loads it in a WKWebView.
• Stops it on quit (SIGTERM, then SIGKILL after 6 s so MCP servers are shut down cleanly). dsh --profile web does not exit when its parent dies, so the app records the server's pid and stops a leftover server on the next launch (after a crash or force quit).
• Starts a fresh server on each launch and loads the login URL it emits. A response from / without that login token does not establish an authenticated session.
• Starts dsh at user-initiated QoS. View → Keep Mac Awake While DSH Runs is on by default to prevent idle sleep during a task and can be turned off.
• Keeps the server on loopback: any other link opens in your default browser.
• Uses a stable local port (3179, falling back to a free one) so the UI's local storage — current session, drafts — survives relaunches.
• Native menus: ⌘R reload, ⇧⌘R restart the harness, ⇧⌘O open in browser, ⌘0/⌘=/⌘- zoom, full screen, standard Edit shortcuts.
• Blends the native titlebar into the harness canvas while keeping macOS window controls.
• Settings… (⌘,) keeps optional Jev and OmniRoute keys in this Mac's Keychain. Both are off by default, and credentials exported by the login shell are not inherited for these integrations. Enabling a switch only forwards that user's saved key to dsh; an actual DSH provider, plugin, or gateway must be configured separately and verified with a request.
• The Swift host sends no telemetry. The installed dsh, model providers, plugins, and user-configured gateways may use the network according to their own settings. Harness settings and sessions remain under $DSH_HOME (normally ~/.dsh).

Requirements

• macOS 15 or later (Apple silicon or Intel).
• DeepSeek Harness installed and on your PATH — follow the official quickstart. The app resolves PATH from your login shell, so if dsh works in Terminal it works here. To point at a specific binary: defaults write io.github.harness-mac dshPath /path/to/dsh

Build

swift test                 # unit tests
scripts/bundle.sh            # universal, ad-hoc signed dist/DSH.app
scripts/bundle.sh --install  # same, replacing /Applications/DSH.app (one copy only)

The first launch of an ad-hoc signed app needs right-click → Open.

The app icon is the harness's own logo, read at build time from your local dsh installation (it is not part of this repository). Without dsh installed, a neutral icon is used.

Headless check

The app can render off-screen, save a PNG and exit — handy for CI and for verifying a change without taking over your screen:

HARNESS_SNAPSHOT=/tmp/harness.png /Applications/DSH.app/Contents/MacOS/DSH

HARNESS_SNAPSHOT_JS is evaluated in the page after it loads, and HARNESS_SNAPSHOT_DELAY (seconds, default 5) is waited before and after it.

Layout

Path	What
Sources/HarnessApp	AppKit app: window, menus, WKWebView host
Sources/DSHKit	Typed Swift client for dsh: web server lifecycle and the SDK stdio JSON-RPC protocol
Sources/harness-smoke	CLI that drives the SDK runtime end to end (harness-smoke <provider> <model> "<prompt>")
Sources/webserver-smoke	CLI that starts and stops dsh --profile web N times and prints boot times (webserver-smoke 6)
Tests/DSHKitTests	Framing, protocol decoding, settings, transcript reducer, URL parsing

webserver-smoke uses an OS-assigned port, checks that the emitted login URL authenticates, and checks that the server stops accepting connections after stop().

python3 scripts/reconnect-smoke.py runs the app off-screen with a temporary DSH profile, terminates only its own server child, checks that the page reconnects, and verifies the replacement server exits with the app.

For a minimal SDK request with a selected effort, set HARNESS_SMOKE_EFFORT before running harness-smoke. The effort must be declared for that model by the installed DSH configuration. Set HARNESS_SMOKE_EXPECT to require an exact synthetic answer; without it, the smoke check can only tell that an assistant message arrived, not that the route actually succeeded.

Notes

See the integration contract for model, effort, OAuth, agent, MCP, and Jev boundaries. The optional Jev Cordis route selector is source code for a user-configured DSH overlay. Its JavaScript file is also bundled under DSH.app/Contents/Resources/Integrations/Jev/; the app does not silently activate it.

• A healthy dsh boot took 3–8 s in local checks. An intermittent DSH boot produced no URL until the watchdog restarted it (35.8 s in an eight-run sample). The app now restarts once after 15 s without a URL and then waits up to 180 s for the retry. The underlying DSH stall remains under investigation.
• The model and effort menus are supplied by the installed DSH Web UI. Custom models show an Effort menu only when they declare reasoningEfforts in $DSH_HOME/settings.yaml. Leaving effort unselected lets the configured route choose automatically. The app does not create a separate model entry for each effort.
• SDK sessions (DSHKit) cannot be resumed across runtime processes; that limit comes from dsh.

License

MIT