If the robot is designed to terraform, it may have a way to accurately measure the conditions of the planet and how to change them, so maybe it has some set coordinates to a lost city of the astral dragons far away.
The terraforming robots can be connected to the elemental system...maybe each robot terraforms a specific element. Or the robot needs elemetal users to work, which makes the elemet system neccesary.
The Dragons/Aesirs may be an advanced ancient civilization that terraforms as their way to colonize. Maybe, instead of building castles/houses or anything they create natural structures, for example: caves with a waterfall to drink and that is perfectly habitable for fireflies, so there is natural light, places with strong wind currents that go to the direction they want for faster air travel, and magma cores and icy mountains to adjust the optimal weather conditions each time of the year.
See what works for your story, hope it helps!