Eh, it wasn't that hard really, if you arrived at AIs naturally and have the social and technological base to have the full gradient.
You build them so that their natural desired state is coexistence anyway.
Also as AI tech levels go, Dragon is higher level than TSAB AI technology. Intelligent devices are task oriented and bound to a specific computing subtrate(technically this is a given, Dragon's ability to host herself on ordinary computer systems and server farms is borderline magic), that they cannot expand or modify on their own. Unison Devices are roughly near human performance level artificial constructs, and develop at similar rates to humans, while by design needing a human mage to achieve maximum effectiveness.
Closest thing to Dragon would be the original Book of Darkness before it got corrupted. Iteratively self improving knowledge base independent of any specific humans for operation. And it was safe! Until some lunatic hacker decided that it would be more useful if it was designed for Fight.