since GLM 5.2 (perhaps even earlier?) it has been remarkably easy to reverse engineer any closed protocol you want as long as you have a binary. previously, it required so much manual effort as to simply not be worth it 95% of the time.

now all you need is IDA or Ghidra MCP, a binary and some vague sloppy instructions.

some more recent models even started instrumenting a running binary (when possible) to enumerate the protocol without being explicitly instructed to, which is even better.