This deliverable focuses on the denition of a common API for the PyCOMPSs programming model and HyperLoom scheduler provided respectively by BSC and IT4I. The objective of the work is to hide the details of the actual task scheduling technology, so that the Multi Level Monte Carlo Python engine is agnostic of the backend being employed. It includes the description of: Common API for calls Examples of usage Basic Documentation The document also contains an initial description on how MPI-distributed data shall be treated from the scheduling point of view.