There isn’t a blanket distinction, in regards to Chol HaMo’ed, between Torah and rabbinic prohibitions. In general, there are three approaches among the Rishonim as to the basis for the restriction on working on Chol HaMo’ed. Some say that it is derived from the Torah but has more areas of leniency than does the restriction on working on Yom Tov. Some hold that its source is entirely rabbinic. There is also a third, fascinating approach, as follows. The Torah decreed that some areas of melacha would be forbidden, yet it empowered Chazal to determine under which circumstances work would be forbidden and under which it would be permitted.[1]
There are significant differences between the laws of melacha on Yom Tov and those of Chol HaMo’ed These differences depend primarily upon the category of melacha of a given act of work, the nature of the act, and its purpose, not necessarily upon whether the prohibition in question is from the Torah or rabbinic. Chazal’s general approach was to distinguish between activity that is related to enhancing the festive spirit of the mo’ed and that which occupies a person with other, tiresome activity.[2] Chazal determined how to apply that general rule, and we are bound to follow their guidelines, which we can be found in the classical sources.
If one studies sugyot of Chol HaMo’ed, he will not find explicit references to the classic laws of muktzeh. (The concept of muktzeh l’mitzvato does, however, arise.) The poskim[3] conclude that, indeed, muktzeh was never included in the prohibitions of Chol HaMo’ed.
In contrast, the rabbinic prohibition of amira l’nochri, which appears primarily in regard to Shabbat, may apply throughout the Torah[4] and certainly extends to Chol HaMo’ed.[5] The logic of forbidding amira l’nochri is that there is a concern that the Jew might come to do the work himself[6] or that involvement in work through a proxy is often not conducive to the spirit of the day.[7] This prohibition applies whether one holds that melacha on Chol HaMo’ed is forbidden by the Torah or is rabbinic.
There are, however, some points of leniency regarding amira l’nochri on Chol HaMo’ed. The most pertinent is: the Magen Avraham[8] says that one may ask a non-Jew to do work in order to facilitate a mitzva that will be needed on Chol HaMo’ed.[9] He explains that since there is an opinion that permits a non-Jew to do melacha on a Jew’s behalf in the case of a mitzva even on Shabbat, one can certainly be lenient on Chol HaMo’ed. The Levushei S’rad[10] understands that the leniency is based on the assumption that the entire prohibition of work on Chol HaMo’ed is rabbinic. Nevertheless, it is generally assumed that one can rely on the Magen Avraham’s conclusion even if one is of the opinion that the melacha prohibition is from the Torah.[11]