The report from the condo up north was simple. Alexa could close the shades. She could set the air conditioning. She could run the scenes. But ask her to turn off a light, any light, and you got nothing. All twenty lights in the place were invisible.

A default that never worked

The root cause was a classic silent failure. The cloud service of Home Assistant has a default rule. The rule must expose whole categories of devices to Alexa. Lights are the most obvious category on that list. On this box, that default never worked. Not once.

Each device with an explicit per-device expose flag synced correctly. That is exactly why the shades and the AC units worked: each one got an individual flag at some point. The lights all rode on the default. The default was a ghost. Twenty devices, all technically “exposed.” Zero devices left the building.

The same bug bit the shades one month earlier. That is the embarrassing part. I met this bug before. I fixed its symptoms. I did not generalize the lesson. This time I flagged every light explicitly and forced a full re-sync to Amazon. All twenty lights appeared in the Alexa app immediately.

Voice only, for Oma and Opa

Then, since I was in there, I did the real project. My in-laws, Oma and Opa, planned to stay at the place alone. They must be able to run the whole place by voice. No app. No dashboard. No calls to me.

That became a full speakability pass. Each device with an ampersand in its name got an “and” alias, because Alexa cannot hear punctuation. The lights in each room got a group, so one phrase moves the whole room. Thirty-seven devices got new aliases, one for each phrasing that two people could try. Their goodnight scene got a one-word alias: “Bedtime.” The house-wide scripts got new names, so their “goodnight” cannot shut down the whole building by accident.

A sunset, not a blackout

The scenes are my favorite part of the whole job. “Oma and Opa Goodnight” does this: the bedroom and bathroom lights fade out slowly, across two minutes. That is not a blackout. That is a sunset. The shades close. The AC settles at 19°. The bedroom speaker starts a white-noise track at a gentle volume.

“Good Morning” reverses it. The music goes off first, so the room becomes quiet at once. The temperature comes back up. The shades open. The lights come on.

Always say degrees

One genuine Alexa absurdity survived all the tuning. Temperature commands only work if the sentence ends with the word “degrees.” “Set the AC to 21 degrees” works. “Set the AC to 21” gets you “I don’t know what went wrong.” Same, Alexa. That rule went on the printed one-page command card on the counter, next to the phrase list. The card is paper. It is the only interface in the house with full uptime.

My favorite automation project this year added nothing. It made the existing system answer to two people who do not need to know that it exists.