Scene Designer
Requires brAIn 1.46
The scene designer, one-off intents and the condition proposal all landed
in 1.46, along with the byte-level edit of automations.yaml that two of them need.
Scenes are the thing everybody means to set up and nobody does. Not because any one of them is hard — because doing it by hand means opening each bulb in turn, picking a colour temperature that will look wrong beside the next one, saving four of them, and then writing the schedule that moves between them.
What makes it possible to do for somebody is that the answer is deterministic. Your registries already say which lights a room has and what each of them can be told, and a mood is a warmth and a level.
Asking for four
Either of:
- Type it into the ask bar: “Design my evening for the living room”, “set up scenes for the kitchen”. The sentence has to name a room; anything that does not falls through to the ordinary ask.
- Pick a room from Design scenes for at the top of the Proposals tab, which lists every room brAIn could compose for with its light count beside it.
The picker only ever offers rooms it can actually do — a control that hands you a choice its own rule forbids is a control that teaches you to distrust it. If no room in the house has two lights brAIn can set, it says that rather than sitting there empty.
Composing is deterministic and costs one read of the house, so a refusal comes back immediately: “the box room has only one light brAIn can set” is an answer you should have before you wonder whether anything is happening. Naming the four is a Claude run, so the offer lands on the tab a moment later.
What each bulb is told, and why it differs
Read from supported_color_modes, never assumed. Four answers, in the order a mood wants
them:
| What the bulb can take | What the scene sets |
|---|---|
| A colour temperature | The mood’s kelvin, and a brightness |
| Colour but not a temperature | The nearest colour to that kelvin, and a brightness |
| Brightness only | The brightness |
| On and off only | On, or off |
A scene of whites is a colour-temperature scene, and kelvin is the control that says so — an RGB approximation of 2400 K on a bulb that could have taken the number is a worse answer written more precisely. A bulb whose modes cannot be read at all falls to the last row rather than being dropped: I could not tell is not it does not work, and the honest thing to do with it is the setting that works on every bulb ever made.
The card says which is which, so a room of cheap bulbs is a set of scenes that still works rather than an empty card.
The number in the file is 0–255, not a percentage
A scene entry is a state Home Assistant reproduces, not a service call. light’s
reproduce-state reads brightness, color_temp_kelvin and rgb_color — a brightness_pct
in a scene is an attribute nothing reads. It would store, load, reload and apply perfectly,
and every light would come on at whatever level it was already at. The percentage is the
vocabulary of the card; the byte is the vocabulary of the file.
The four moods
Morning is cool and bright — it is the one that has to wake somebody up, so it is cooler than day on purpose. Day is neutral and full. Evening is warm and dimmed. Night is the only one that turns most of the room off.
Which light stays on at night is matched on its name — night, bedside, hall, landing, as whole words. There is no attribute for “this is the one I leave on”, and inventing a rule from the wattage would be a guess about your furniture. A room with nothing named that way goes fully dark, which is what night means in a room without a nightlight in it.
The numbers are plain and fixed rather than a model’s choice. A set of scenes that came out different every time it was offered would be one nobody could reason about.
The card is a picture
There is no replay and no trial week here — nothing in the last month set these scenes, so there is no week to grade them against. The evidence is what the room will look like:
- A swatch per light per mood, four rows, drawn from the colour the bulb will actually hold.
- A light that is off in a scene is an empty outline, not a dark square, because a dark square on a dark panel is indistinguishable from a very dim one.
- The lights named in text under the strip. A phone has no hover, and which bulb is which is the whole reading.
- Anything on your
protected_entitieslist is shown as Skipped: protected, not quietly left out. Seeing that brAIn knows the lamp is there and knows it may not set it is the point of showing it. Protection is asked at the producer as well as at the writer — a card offering something brAIn will refuse to write is a wasted no.
Saying yes
Accepting writes all four at once — four moods are one decision and one press, and offering them one at a time would be four cards you have to answer consistently for the set to mean anything.
They go into scenes.yaml by the same five steps an accepted proposal uses against
automations.yaml: snapshot into the edit journal, append with your
file above them untouched, scene.reload, then wait for all four scene. entities to
turn up in Core — because three out of four is a mood missing from a schedule nobody has
written yet. If any of that does not happen the file goes back and the card tells you what it
tried. Undo takes them straight out again.
The same refusals apply, in the shape this file needs them:
- No
scene: !include scenes.yamlin yourconfiguration.yaml. Without that line brAIn cannot tell where this house keeps its scenes, and appending to a file Home Assistant does not read is a change that silently does nothing. The refusal names the line it looked for. - A
scenes.yamlthat is not a list of scenes. An empty or missing one it creates. A file holding nothing but a comment header is empty, not unreadable — that is the ordinary case on a house that has never saved a scene, and it used to be refused. - A duplicate id or name already in the file.
- A protected light, asked again here because a file the panel writes never passes through the chokepoint that normally enforces that list.
Two rooms are refused, each with the reason
- Fewer than two lights brAIn can set. Four scenes over one bulb is four ways of saying the same thing. If the rest of the room is protected, the refusal says so.
- More than forty. That is a floor rather than a room, and brAIn would be composing moods for a building. Split it into areas and ask again.
Claude names them, and only that
One optional run, two turns, four lines: a name a person would use out loud about their own home, each under 24 characters, shown beside the room’s own name. All four or none — three good names and one that came back as “4.” is a set with a hole in it.
If the run fails you get Morning, Day, Evening and Night, which work perfectly well. Nothing about which bulb takes which kelvin is a model’s decision: that is composed from the registries, because a model choosing it is a guess wearing a config and one nobody can check by looking at the card.
Then the schedule
Once all four scenes really exist, brAIn offers a second proposal: the automation that walks the room through them.
It is offered off scenes.yaml rather than off the proposals store, deliberately — what makes
the schedule sayable is the scenes being there, and somebody who copied the card’s YAML in by
hand has earned it exactly as much as somebody who pressed the button. A schedule naming a
scene that is not there is an automation that errors at seven every morning.
Unlike the scenes it is an ordinary automation, so it can be tried for a week — which is itself a replay of the days you have just lived, graded against what you actually did.
Two of its four times are measured and two are not, and the card says which:
| Mood | When |
|---|---|
| Morning | The wake time brAIn has measured for this house |
| Day | 11:00 — a fixed guess |
| Evening | 18:30 — a fixed guess |
| Night | The measured settle time |
Nobody’s first press of the day is at noon, so midday and the early evening are not things brAIn can see. They are stated as the guesses they are, and they are yours to change once the automation is in your file. If brAIn has not gathered enough days yet, morning and night fall back to 07:00 and 22:30 — and the card says that too, rather than presenting a default as a measurement.
Where to see it
- The Proposals tab, with a Scenes pill on the card and the room picker above the list.
GET /api/scenes/areas— the rooms that qualify, and how many lights each has.- ⚙ Diagnostics carries how many sets have been designed and how many asks were refused, because an empty tab reads the same either way.