The framework has built-in support for constructing data sets for force field optimization and assessment via two main routes. Data sets may be manually transcribed by a user by directly creating the data set objects, typically requiring the user to enter common information about a property such as the state for which it was measured, the composition of the measured system, provenance information, and so forth. More usefully for large-scale projects, data may be automatically imported from certain sources. The framework currently supports importing data directly from the FreeSolv data set , and from the NIST ThermoML archive .