title_body: What tools exist for creating syntactically correct generated text in new languages?
upvoted_answer: It is difficult for a machine to passively understand a language (it takes tons of time with machine learning, and that's for Google). Actively, that's even more difficult, as many machine responses are pre-programmed and rarely actually generated (and in that case, mostly nonsensical, but the question isn't for sensical utterances). It will be extremely difficult and without appropriate backing impossible to make one that learns a new language.
  
  That said, the one like the Toki Pona in your question could be made. But you'd have to program most of it yourself, and in languages like Toki Pona that's easy. Try generating artlangs which more like natlangs.
  
  This doesn't mean it couldn't seem like one. You could:
  
  
  Extract text (in English or some language) from books or such. You can find enough text online.
  Translate it (i.e. Google translate) between many languages, obscuring the information. (optional)
  Translate it from English&mdash;or better, i.e. Lojban, Esperanto, Toki Pona or raw predicate logic, as they are less complicated and easier to translate from&mdash;to your conlang.
  Dispose of invalid sentences using some kind of lightweight parser. (optional)
  
  
  I couldn't find any (good) generators, but you could have the first!