What is the view of the majority of Sunni and Shia scholars on the authenticity of Hadith Qudsi? Are such narrations common to both?
Further clarification:
There are many different hadith that are considered hadith qudsi (that is, telling us directly what God says, but not as part of the Qur'anic revelation).
Some of these hadith are shared between Sunnis and Shi'is, and some are specifically Sunni, and some are specifically Shi'i.
As mentioned in the previous answer, each one can be evaluated individually with respect to its authenticity.