[Home](./index.md) > [@keymanapp/kmc-model](./kmc-model.md) > [LexicalModelSource](./kmc-model.lexicalmodelsource.md) > [rootClass](./kmc-model.lexicalmodelsource.rootclass.md) ## LexicalModelSource.rootClass property The name of the type to instantiate (without parameters) as the base object for a custom predictive model. **Signature:** ```typescript readonly rootClass?: string; ```