Psionic Spellcasting and Stealth

[ecarden]

So, question. The Swarm of Cranium rats has psionic spellcasting and telepathy, but no speech:

"Spellcasting (Psionics). As long as it has more than half of its hit points remaining, the swarm casts one of the following spells, requiring no spell components and using Intelligence as the spellcasting ability (spell save DC 13):

At will: command, comprehend languages, detect thoughts

1/day each: confusion, dominate monster"

If the swarm is hiding and casts dominate monster on someone, does that break stealth? It does have a vocal component, but given the nature of the creature and the spellcasting, it seems like it would be silent? What about the somatic component? I'm assuming if you can't see the rat, you can't see the rat's head move.

What do folks think?

[RSP]

I think it’s still hidden, both RAW and how I would play it:

“You can’t hide from a creature that can see you clearly, and you give away your position if you make noise, such as shouting a warning or knocking over a vase. An invisible creature can’t be seen, so it can always try to hide.”

As the casting isn’t making noise, I don’t see why it would break being hidden.

[Devils_Advocate]

It says "requiring no spell components" right in the text that you quoted. Not "requiring no material components". Verbal and somatic components are spell components, so they're not required.