I am wondering a couple things though.
1. I read that in like D&D 2e and previous there was no perception/spot check and you had to actually say what your doing in the room?
There were specific abilities like the thief had for detecting traps and elves detecting secret or hidden passages on a d6 roll. If you really dig into the DMG and PHB you also find little rules here and there for things. There was more of an emphasis on interacting with the scenery. So the elf might get that d6 roll automatically for just being near a secret panel, but they didn't want to discourage People from describing how they investigate a chamber (i look under the bed, or i turn the statue around). The approach to social interaction was similar. There wasnt a diplomacy or bluff skill in 2E. They had etiquette, but that was a knowledge roll (it specifically said it couldnt be used to replace roleplaying).
That said, ability checks were a big gap filler if you needed to roll for that sort of thing. So you might make a wisdom check to see people spot something. I 2E you just had to roll under your ability score to succeed (non-weapon proficiencies worked the same way).
There were also non-weapon proficiencies for non-combat (they were were optional) and two other optional skill methods.