I believe it gives a small amount of defense experience, I may be wrong but I think it was changed with addy gloves from RFD? It may be Murder Mystery or the addy glove subquest that give def exp, but I'm thinking that the Nature Spirit quest is where def exp is obtained. Anyone mind looking into this? Thanks.
Also:
I suggest on the magic guide adding what to do under the training section. It gives training areas, but not how to train. Levels 1-55, curse; 55-68, alch; 68-99 alch or lvl dragonstone enchantment at mage training arena. (If anyone knows more spots or ways to train magic feel free to add to this, Lunars supposedly had a great way to train mage.
Additionally, like with the fletching guide, the quests for skill exp is quite nice.
I will try to update this with more info.
Update: RFD has a link to the agility guide for more information on the Ape Atoll agility course, except there is no information on the AA agility course. I will go through and gather screenshots if you need, or if theres a guide pending to be added, add it
Cold War Guide: Feel free to edit this as you will. Added text information would be nice. Edit my poor grammar, make it more interesting please lol. Needing someone to code this and add to agility guide when it is complete.
Introduction: After completion of the Cold War quest, access to the agility arena located there is granted. It is a nice spot for the mid levels, offering easy experience.
First Part of the Course: Here are big sliding rocks called breakers, they slide in a constant patern, the goal is to pass them and not get hit when they slide.
Part 2: Click on the stepping stone to climb up, the objective here is to jump from all the stepping stones to the end.
Part 3: Tread the icicles, if you simply click to walk by them you will get hit. Tread softly over them to pass.
4: Climb the ice path. Failing will result in sliding down to the ice square you were on, 2 damage.
5: Next you watch a cool animation of you as a penguin flying down a ramp, exit the course to receive course completion experience.
Here is a handful of pictures, pick and crop the ones you want to use as you please.
Exp table, even though its not really a table

:
Sliding rocks 55
Stepping stones 80
icicles 40 per icicle
ice path 180
course completion 65
total: 540