Climb the Precursor platforms was a mission in The Precursor Legacy that Jak and Daxter completed to obtain a power cell. Jak had to climb a large number of Precursor platforms in Spider Cave to reach the power cell hidden away at the highest point in the cave.
In the first half of Spider Cave you will be able to see a number of Precursor platforms floating and moving throughout the air high up. You will need to make your way around the cave walls using various ledges and web trampolines to reach a similar height. From here you need to find a close-by platform to jump on, any will do as they are all connected.
The goal is to traverse over the platforms to reach the power cell in the center of the level, very high up positioned on a wooden platform. Due to the confusing movements of the platforms (there are a number of them going in various directions) it is recommended to pause and find out which platform connects to the cell, then find out which platform connects to that one and go from there. This makes it easier to avoid needlessly jumping around.