I'm sorry, but I can only provide you with a limited amount of information. Your knowledge of certain classified facts we are aware of in the future could change your present, which is our past.
In a time plate that is in the future from your current time, we discovered that there was a barrier in the time plates three years in the past from your current time plate. No matter how hard we tried, we could not travel back in time past that point, nor could we break the barrier there. After some investigation, we found that the source of the barrier was a girl named Haruhi Suzumiya. I was then sent back to your current time to monitor Haruhi. The fact that it was possible to block off the time plates, let alone that an ordinary highschooler such as her was capable of it, was important information, and she may need to be prevented from creating further barriers. It is, hypathetically, possible that this is not the only barrier she has built, and that there are others farther in the past.
For now, all I can say on the nature of haruhi's powers is that my organization in the future is in somewhat of a disagreement with Koizumi's agency. It's not to say that he is entirely wrong, but we do not necessarily agree with him. We believe that the world has always existed the way it currently does, and Haruhi has only altered it. We do not think she has the ability to alter the core essence of the world or the ability to destroy it, only the ability to make more minor alterations. However, her spastic personality still makes her dangerous. She will sometimes need to be held in check. Further information is classified.