This kind of encoding[0] is ubiquitous in networking protocols. It scales down to small silicon well and enables the receiver to estimate resource requirements or skip parts of a serial byte stream without storing it in memory first. These encodings usually aren't aligned by design.

[0] https://en.wikipedia.org/wiki/Type–length–value

It's called TLV encoding - tag/length/value. It's very common in all sorts of network protocols and serialisation formats. It allows you to skip unidentified tags. Sometimes, like in the PNG file format, there's a fixed bit in the tag that tells you whether it's safe to skip or if you have to reject the whole thing because you don't understand this tag.

Hey dang can I get my rate limit turned off pretty please?