What's the text encoding for the Metadata JSON?

[plutoscarab]

Is it UTF-8, ASCII, something else?

[plutoscarab]

I see that JSON spec requires UTF-8, but I have a different question. Looking at sample terrain tiles served from Cesium, I see that the metadata body has it's own nested length header, e.g. 68 bytes of JSON has an extension length of 72, which includes the 68 bytes plus 4-byte header with the integer value 68. That's not clear in the spec.