Who administers direct democracy mechanisms at the national level?

Constitutionof 2014

https://www.constituteproject.org/constitution/Tunisia_2014.pdf

Article 126: Mandate

The elections commission, named the SupremeIndependent Elections Commission, is responsible for the management andorganization of elections and referenda, supervising them in all their stages,ensuring the regularity, integrity, and transparency of the election process,and announcing election results.