home-assistant/core · warning · HomeAssistantError

This device does not support setting brightness

Error message

This device does not support setting brightness

What it means

Raised by BondBaseLight.async_set_brightness_belief when a brightness command arrives for a Bond light whose device profile lacks the set_brightness capability (self._device.supports_set_brightness() is False). It is a capability guard, not an API failure: the command is rejected locally before any HTTP call.

Source

Thrown at homeassistant/components/bond/light.py:84

        for device in hub.devices
        if DeviceType.is_light(device.type)
    ]

    async_add_entities(
        fan_lights + fan_up_lights + fan_down_lights + fireplaces + fp_lights + lights,
    )


class BondBaseLight(BondEntity, LightEntity):
    """Representation of a Bond light."""

    _attr_color_mode = ColorMode.ONOFF
    _attr_supported_color_modes = {ColorMode.ONOFF}

    async def async_set_brightness_belief(self, brightness: int) -> None:
        """Set the belief state of the light."""
        if not self._device.supports_set_brightness():
            raise HomeAssistantError("This device does not support setting brightness")
        if brightness == 0:
            await self.async_set_power_belief(False)
            return
        try:
            await self._bond.action(
                self._device_id,
                Action.set_brightness_belief(round((brightness * 100) / 255)),
            )
        except ClientResponseError as ex:
            raise HomeAssistantError(
                "The bond API returned an error calling set_brightness_belief for"
                f" {self.entity_id}.  Code: {ex.status}  Message: {ex.message}"
            ) from ex

    async def async_set_power_belief(self, power_state: bool) -> None:
        """Set the belief state of the light."""
        try:
            await self._bond.action(

View on GitHub (pinned to 58a3fdb3ea)

Solutions

  1. Remove brightness attributes from automations/scripts/scenes targeting this entity, or target an entity that supports brightness.
  2. Check the device's Bond properties (actions include 'set_brightness') in the Bond app to confirm the capability.
  3. If the physical device does support dimming, re-add it in the Bond app so its profile carries set_brightness, then reload the integration.

Example fix

// before
await entity.async_set_brightness_belief(128)
// after
if entity._device.supports_set_brightness():
    await entity.async_set_brightness_belief(128)
else:
    await entity.async_turn_on()
Defensive patterns

Strategy: type-guard

Type guard

def supports_brightness(entity) -> bool:
    """True when the Bond light accepts brightness commands."""
    device = getattr(entity, "_device", None)
    return bool(device and device.supports_set_brightness())

Try / catch

try:
    await light.async_set_brightness_belief(value)
except HomeAssistantError as err:
    if "does not support setting brightness" in str(err):
        await light.async_turn_on()  # graceful fallback to on/off

Prevention

When it happens

Trigger: A light entity built from a Bond device with only on/off actions receiving set_brightness_belief(brightness > 0) — e.g. an automation or scene storing a brightness for an on/off relay/light, or a restore-state replay.

Common situations: Script or scene sets brightness_pct on a plain on/off light; Google Home/Alexy sync sending brightness for a dumb light; restored state from when the device previously supported brightness.

Related errors

AI-assisted analysis of home-assistant/core@58a3fdb3ea (2026-08-14). Data as JSON: /api/errors/4b24cf686e5178d5. Report an issue: GitHub.