Does a Homunculus need to sleep? If not, does that mean it can work as an alarm?

Question

One of my players, a Cleric Gnome, just got a Homunculus as a pet companion.

The Homunculus is a construct, and as far as I know, constructs do not ever need to sleep. Is that correct for Homunculus too? (I have a doubt since the description does not say it is immune to the Sleep spell.)

Does that make the Homunculus a great alarm in case the Gnome gets sneaked upon while sleeping? I would imagine that the Homunculus can wake the Gnome up by making noise, slapping him, etc. whenever something unusual happens during the night (However, I would imagine that its thoughts would probably just integrate the Gnome's dream and not wake him up...)

Answer 1

Does a Construct need to sleep?
In the general case, no.

Does a homunculus need to sleep?
Probably not, but it's open to a DM ruling. It would be reasonable to rule that a Homunculus need not sleep, since it is a construct.

From MM pages 19 / 166: Constructed Nature (Animated Object / Golem)

"An animated Object (or Golem) doesn't require air, food, drink, or sleep."

MM page 188:

Homunculus, tiny Construct

A Homunculus is a construct."

MM page 6:

"Constructs are made, not born."

When we look at other constructs like Animated Objects and Golems, they don't sleep, so it's reasonable to rule that a Homunculus need not sleep and thus be a great alarm clock/alarm for a gnome who needs his beauty sleep.

Caveat: Modrons, Animated Objects, and Golems are not presented as having immunity to sleep, nor are homunculi. A save versus sleep might be necessary were the spell cast upon them. ("Sleep" / "Asleep" are not conditions. The sleep spell creates the Unconscious condition).

Counter Argument: since the line "constructed nature" is not included in the description, as it is for other constructs, it isn't treated as a construct for that particular case of "constructed nature."

Recommended Ruling: it does not need sleep since it is a construct.

Put another way: you can put a Homunculus to sleep, but it doesn't need sleep. (No amount of beauty rest will make it any prettier. It's an ugly baby that only its creator could love ...)

Answer 2

RAW it is undefined.

The homunculus is a construct type but:

A monster's type speaks to its fundamental nature. Certain spells, magic items, class features, and other effects in the game interact in special ways with creatures of a particular type.

There is no general rule that construct's don't sleep or require nutrition etc. This is called out in specific descriptions (e.g. Golem) but not for the homunculus.

The homunculus is vulnerable to a Sleep spell because there is nothing in the rules that gives it immunity. Time for the DM to make a ruling about natural sleep.