Spell-like Proficiencies - declarations required?

So I’m looking at rolling either a mod-nightblade or a ridiculous kung-fu monk class using proficiencies/custom powers that let you use spells at certain intervals (per ACKSPC 98). I’m curious, though - if one intends to use such a proficiency in combat, does it require pre-declaration like any other spell? Likewise, can it be interrupted? My natural inclination is yes to both (as the wording is “grant the class the ability to cast a spell”, which suggests that all normal casting limitations should apply), but I just sort of want to make sure.

Yes, it’s intended to be a spell-like casting, similar to using a scroll.

To build a spell-like proficiency that is available as an action in lieu of attacking, treat the spell as one level higher than it is for purposes of availability.

Excellent. Thanks Alex!