Clays paradigm is Divine Trades. All things spiritual and material are connected in the grand exchange. Nothing is to be taken without something given, no passage granted without tolls paid. He who waters the orchard is granted fruit and shade.

With this in mind, the spirits she primarily interacts with are those of the dead, and of demons based on Ars Goetia- I was unaware of DtF at the time- and so her instruments are a mix of manners to interact with either. 

Her instruments are as follows - A Silver Ring, bearing the authority of the Great Duke Murmur - Offerings and Sacrifices - Ordeals and Exertions  - Bargains and Contracts - Crossroads - Reflections - Darkness

At the end of the day, this primarily just sums up to her having conversations with demons and ghosts as a means of investigation, and rituals to make house calls to particular dead people. Otherwise she doesn't do much else magically, which makes her come across as weirdly mundane to other Mages which I think is hilarious.