One would think their would be a glyphic description of the device and its function or at least its results in a tomb or somewhere.
Maybe the glyphs and paintings are there, but not recognized for what they are. I mean, what “scientific” archeologist would recognize an engineering drawing?
I believe the only glyphs inside the pyramid are some numbers found in a shaft that only a robot can reach. These numbers appear to be a measurement of the length of the shaft.