Hi there,
There are many competing standards on how one should create a component library.
But we use/require the conventions laid out by KiCad as listed under klc.kicad.org
Generally:
- The first pin should be located in the top left corner.
- Polarity markings should follow the IPC-7351B rules, also highlighted in this article from us: Component Orientation and Polarity Rules for Assembly
- The origin should be in the center of the component or where highlighted by the manufacturers. (Exceptions may apply for super specific parts.)
- Stencil apertures should follow the recommendations by IPC-7525 we also have an article on that: Stencil aperture design
Currently we do not read the component height from the EDA data.
I hope this overview helped 