The Host Window

The JetWhale host is one window: a sidebar down the left side that picks what you are debugging and which tool you are looking at, and the selected plugin's own UI filling the rest.

Everything below is the host itself — the plugins it shows are documented on their own pages (Network Inspector, Nav3 Navigator, Compose Semantics Inspector, Storage Inspector, Debug Actions, Device Mirror).

Plugins that need no app

Plugins that need no app ("requiresAgent": false — Device Mirror, for one) are listed at the top of the sidebar, above the app picker and apart from it by a divider. They are usable as soon as the host starts, with nothing connected, and stay one click away whatever app is selected below: switching apps never moves one that is on screen, and the debug server restarting does not close it. Each of these plugins runs once, not once per connected app.

Over MCP they live in a session of their own, host, which jetwhale.listSessions always lists first, named Host.

Choosing an app

Below the divider, sessions are picked with two dropdowns, because one host commonly holds several apps from the same device:

1. Select Device — one entry per device, keyed by the deviceId the agent reported. Sessions that share a device are grouped under it.
2. Select App — the apps connected from that device. It only appears once the device has more than one app (or one is already selected). Picking a device automatically selects its first app, so a session is always active.

Each entry carries a small lock icon for how its transport is secured — see Session security indicator. When nothing is connected the device row reads No app connected.

When a session goes away the host says so (<device> · <app> disconnected, or N sessions disconnected when several drop at once, e.g. after a debug-server restart).

The plugin list

Under the picker are the selected app's plugins; the plugins that need no app, above it, are listed the same way. Enabled plugins come first. The rest follow in two greyed groups at the end, each under a light fold row that expands in place:

• N disabled — installed but switched off; open to begin with unless there are more than two. Hovering a row says Disabled — click to enable; clicking opens a screen with an Enable button, and the plugin opens as soon as it is enabled.
• N not in this app — installed in the host, but the selected app's agent never advertised the plugin id; folded to begin with. Clicking one opens a screen that says how to add it to the app: the Gradle dependency of its agent library and its register(...) call to copy, with a link to the plugin's guide for official plugins. The plugins that need no app never land here.

With no app connected, the lower list says Connect an app to see its plugins. instead.

Click an enabled plugin to open it. Every row except a "not in this app" one carries an overflow (⋯) menu:

• Disable / Enable — the same toggle as jetwhale.setPluginEnabled over MCP, applied host-wide rather than per session. This is the only entry a disabled row's menu offers.
• Pop out — moves the plugin into a window of its own. The main window shows This plugin is popped out. Please check the separate window. with a Bring back to main window button, and the sidebar entry's menu switches to Bring back. Popping out is how you watch two plugins (or the same plugin on two sessions) side by side. A plugin that renders no UI has no scene to move, so the entry is not offered for one.

If no plugins are installed at all, the sidebar says so and — when some jars failed to load — offers a shortcut to the plugin settings screen. See Host Settings → Plugins for installing them.

MCP badges

A plugin that contributes MCP tools carries an MCP badge on its sidebar row. Clicking the badge opens the MCP tools browser already filtered to that plugin and to the session currently selected.

While an AI agent is actually calling one of that plugin's tools, the badge fills with the accent color and the whole row takes an accent-colored rotating ring, so the plugin being driven is unmistakable even if the label has scrolled out of view.

AI activity

The sidebar header shows whether an AI agent is connected over MCP; with none connected it holds only the collapse control. While one is connected it reads AI agent connected; while a call runs, a rotating ring goes round the header's banner and the tool's short name (mirror.tap) takes the text's place, with the full name on hover. The header keeps its height either way, so nothing below it moves. Clicking it opens the details — the tool, the plugin it operates, the app — and the Follow the AI switch, the same setting as AI Activity. On the collapsed rail only the icon is shown, with the ring round the icon.

The sidebar footer

Entry	What it opens
Browse MCP tools (wrench icon)	The MCP tools browser, unfiltered — so the tools an agent can reach are visible without first finding a plugin that publishes some.
Settings (gear icon)	Host Settings.
About JetWhale (info icon)	The about panel: version, project links, and OSS Licenses — the full list of open-source components the host ships.

When a newer release is available, a banner appears above the content with a View in Settings shortcut. Updates are never applied automatically — see Host Settings → Application.

Collapsing the sidebar

The collapse button in the sidebar header shrinks it to a narrow icon rail; the same button on the rail expands it again. Collapsed, it keeps the same entries as icons — the session picker, the plugin list, and the footer's MCP tools, Settings and About buttons — but shortened: the rail lists only the enabled plugins, with no grouping and no overflow menu, and its session picker is a single flat list of device · app rather than two dropdowns. Every icon names itself in a tooltip.

The log viewer

Settings → General → Application → View Application Logs opens the host's own captured stdout/stderr in a separate window: filter by substring, toggle auto-scroll, and clear the buffer. This is the host's log, not the debugged app's — it is where a plugin jar that failed to load, or a server that failed to bind, reports itself. The same buffer backs the jetwhale.getLogs and jetwhale.clearLogs MCP tools.