Using ctx stable

The domains below are available now. For what's still being designed (ctx.ui, ctx.settings, ctx.storage, ctx.theme, …) see the Roadmap.

You write an Extension and the host calls its activate(ctx) once, handing you an ExtensionContext — ctx. Everything your extension does flows through ctx, and it comes down to three things:

Group	What it's for
Registration	add things to the app — editors, panels, commands, status items, menus, keybindings…
Services	read & drive the running app through typed domain services
Other	invoke commands; consume other extensions' APIs; identity

New here? Start with the guide. Otherwise drill into a method below — each page has the signature, an example, and links down to the type definitions.

Registration

Add things to the app. Each method takes a typed object and returns a Disposable (the host also tracks it on ctx.subscriptions, so teardown is automatic).

Method	Adds
ctx.registerEditor	an editor (presenter) for a file type
ctx.registerSidePanel	a left/right column panel
ctx.registerStatusItem	a status-bar widget
ctx.registerCommand	a named, invokable action
ctx.registerKeybinding	a shortcut bound to a command
ctx.registerMenuItem	a command in an application menu
ctx.registerFileType	declarative file metadata
ctx.registerDockPanelKind	a center-dock tab kind
ctx.registerSettingsPage	a page in the Settings dialog
ctx.registerThemePreset	a selectable theme in the picker

Services

Read and drive the running app through typed domain services — never by importing the store or touching the platform directly. Opening files lives on ctx.editors (not ctx.workspaces).

Member	Purpose
ctx.editors	open files into editor tabs; save / saveAs / closeActive; registerSaveHandler (EditorService)
ctx.terminals	open / reap terminal tabs (TerminalService)
ctx.workspaces	workspaces & editor tabs (WorkspaceService)
ctx.layout	side-panel collapse state (LayoutService)
ctx.files	read / write / list / watch the filesystem, host-mediated (FileService)
ctx.process	persistent process / PTY sessions that survive restarts (ProcessService)
ctx.search	cross-file content search over the workspace (SearchService)
ctx.theme	presets + active theme + custom themes (ThemeService)
ctx.dnd	drag sources + drop targets with typed payloads (DndService)
ctx.ui	native pickers + toasts + menus + modals (confirm / prompt / showModal) (UiService)

Other

Member	Purpose
ctx.executeCommand	invoke any registered command by id
ctx.getExtension	consume another extension's published API (ExtensionHandle)
ctx.extensionId	this extension's id (read-only)
ctx.subscriptions	the Disposables the host tears down on unload
useServiceState	React hook to read any service's reactive state (ReactiveService)
useFocusGroup	React hook for keyboard nav of a focus group — list / menu / toolbar: one tab stop, arrows, the keyboard ring
focusGroupNextIndex	the pure roving-index helper useFocusGroup runs — for widgets that can't use the hook (e.g. menus)

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Looking for a type? The full, generated type reference lists every interface and type alias in the SDK.