Syntax maker is the natural language generation tool for generating syntactically correct sentences in Finnish automatically. The tool is especially useful in the case of Finnish which has such a high diversity in its morphosyntax. All you need to know are the lemmas and their parts-of-speech and syntax maker will take care of the rest.
Hämäläinen, Mika and Rueter, Jack 2018. Development of an Open Source Natural Language Generation Tool for Finnish. In Proceedings of the Fourth International Workshop on Computational Linguistics of Uralic Languages, 51–58.