It's a 3 bit quant of Llama3-8B. I'm sure there are use-cases for that, but it's useless when it comes to tool calls or coding and I wouldn't trust it's factual accuracy either.
JSON 5 is pretty good. It just needs to make the top-level brace and all commas optional, and add proper support for multi-line strings (writing '/n/' at the end of every line doesn't count).
Allowing only valid JavaScript identifiers to be unescaped keys is also a bit quirky (You have to quote reserved keywords).
But they will never change any of that because it would break JavaScript compatibility.