An altar servitor is best thought of as giving your Altar a computer or AI like interface.
An Altar Servitor makes your altar much more interactive like a familiar that you cast spells with, rather than as a static object you do spell work on.
An Altar servitors primary function of an altar servitor is to perform routine maintenance on your existing spell work helping it operate more smoothly by acting as a facilitator to smooth out unforeseen circumstances or obstacles to your workings.
Given a proper amount of complexity in its ability to process information an Altar servitor can perform spell work on its own provided you give it proper instruction and access to the necessary materials
I have used several methods to create or restart an existing Altar Servitor as I have moved from one location to another and experienced a lot of trial and error in this process.
I have found that it is best to give your Altar servitor a sigil, which helps strengthen and define its form but also gives you a means of accessing your altar and its spell work remotely through the serivitor program. You can think of this sigil and your serivotrs remote control. I draw this sigil on every object on my altar that is connected to the servitor program. You can also use this sigil to restart an existing Altar should you move, or have to temporarily take down your altar for some other reason.
An altar servitor does not require a vessel because the altar itself is the serivitors vessel, however it will need both a power source and a “Brain” as a way to process information.
The battery aspect does not need to be complex as long as you are working with the altar daily, a Quartz crystal designated as a battery and placed on the altar will suffice. Myself I use a combination of crystal gardens and “seriviotor tanks’ ‘ as shown in this video here. * * in which I am using simple life forms as both a power source and a natural processing center for the servitor program.
My first Altar Servitor i actually used the CPU i removed from an old computer as the processor, however i have found that organic material works best, besides the servitor tanks and minions, i have several skulls, crystals,, and even preserved brain Matter dedicated to this purpose. So far I have not found any problems with using multiple power sources and processing units at once, it only seems to add to the servitors ability to process more and more complex information and thereby enable them to perform more advanced tasks.
Maintenance of an altar servitor is simply to use your altar and give the servitor task to perform. Allowing the Sevitor to have a sense of self can also improve its function and ability to make problem solving decisions but must be considered carefully and very definite parameters set to any personality you allow it to develop. This is of course important with any created being, but in my experience Altar Servitors once given a sense of self tend to develop a very strong instinct for self preservation which needs to be kept in check if you are not in a permanent living situation or need to move your altar from time to time. However using a sigil connected to the Altar servitor should help to mitigate its survival instinct during such times.