I was watching my dad play Ocarina of Time again, and it occurred to me.....there's nothing to tell you that you need to go find the Ocarina in Dampé's grave in order to get into the Forest Temple. You just have to know that that's what you need.

I am aware that if you enter Dampé's house as a kid and read his diary he mentions "something that grows and shrinks," obviously referencing the hookshot that you get from his grave later on, but there's no way to know (unless you've already played the game) that the item that "grows and shrinks" also allows you to pull yourself up to unreachable places.

Is there any real clue that tells you that the next thing you need to get is the hookshot? If there is something, please let me know!

Navi will probably whine about it 24/7 until you get it.

I seem to remember that Sheik meets you in the Master Sword room and tells you that there is something you need in Kakariko Village.

Btw, random glitch screenshot I made of Majora's Mask a while back (somewhat related )

Yeah, I guess you're right that they intentionally withheld information about the whereabouts of items, but for the sword you know it HAS to be somewhere within the small area of the forest, leaving you only a few places to look.

I think he was talking about the first Zelda game. In it, the sword is in a cave that can be accessed from the first screen you come to, but you can choose to ignore the cave and continue without a sword.

I think what they might have also tried to get you to do was Read the Freakin' Manual. Ocarina of Time's instruction manual discusses some of the most important items in the game, including the Hookshot. It tells you that you can reach unreachable locations with it, and that it shrinks and stretches. That, combined with your knowledge that Dampe has the "stretching, shrinking keepsake", will let you know where to find the Hookshot.