Scenes & Service Groups

Scenes and service groups let you control multiple devices with a single action.

Scenes

Scenes are predefined groups of device states set up in the Apple Home app — for example, "Good Morning" might turn on the kitchen lights, set the thermostat to 21°C, and unlock the back door. Once a scene exists in Apple Home, Homecast can run it from anywhere.

Where scenes appear

• Dashboard — scenes for the selected home appear in the sidebar. Click a scene to execute it.
• Mobile app — scenes are listed alongside rooms.
• REST API — POST /rest/scenes/:id/execute (by UUID) or POST /rest/scene with {home, name} (by name). See the REST reference.
• MCP — the run_scene tool is exposed to AI assistants. See the MCP reference.
• Automations — the Run Scene action executes a scene as part of a Homecast automation.

Creating scenes

Scenes are created in the Apple Home app, not in Homecast. Open Apple Home → tap the + icon → Add Scene, pick the devices and target states, save. The scene appears in Homecast within a few seconds.

Service groups

Service groups are HomeKit groupings of multiple accessories that act as one — for example, "All Living Room Lights" toggles every light in the group together. Service groups are useful when scenes are overkill (you just want a single combined control) or when you want a group to appear as a single widget on your dashboard.

Where service groups appear

• Dashboard — service groups appear as a single widget that controls every member.
• REST / MCP — service groups are addressable just like accessories.
• Automations — both triggers and actions can target a service group instead of a single accessory.

Free plan

Service groups count as a single accessory toward the free plan's 10-accessory limit, no matter how many devices they contain. See Account & Settings.

Creating service groups

Like scenes, service groups are created in the Apple Home app. Long-press a tile → Group with Other Accessories → pick the accessories → name the group.

Scenes vs service groups

	Scene	Service group
What it does	Sets specific values on multiple devices (e.g., 50% brightness, lock door, set temp)	Controls multiple devices in unison (on/off, brightness, etc.)
Per-device target values	Yes (each device can have its own state)	No (all devices share the same on/off/brightness)
Appears as	A button you press to run it	A regular widget you can toggle and adjust
Best for	"Good Morning", "Movie Night" — multi-device routines	"All Living Room Lights" — unified control of similar devices

Troubleshooting

Symptom	Fix
New scene/group not appearing	Wait 30 seconds, then reload the dashboard. Apple Home changes propagate via the relay.
Scene runs partially	Some devices may be unreachable. Check the Apple Home app to see if all devices respond there first.
Group toggle doesn't work	If a group contains mixed device types, only common controls (on/off) are exposed. Check the group's members in Apple Home.