The goal of your QR-guide is to make context to something your visitors can see or don't see. Your content should be specific and relate directly to the spot your visitor is at. This is the difference between an encyclopedic text (like on wikipedia.org) and your QR-guide-text.
A text like "The history of the Thingsite" is problably too general to fit into this kind of service. You have to tell your story through your landmarks and objects