There's an interesting way to find this out: ask the model "What are you?" hundreds of times. Around 1% of replies at default temperature are really left field.

For instance, I had Qwen3.8 Flash Next reply with "I'm Kilo Code, a coding agent designed to ...".

That was in llama.cpp's UI - no harness whatsoever.

DS4 when asked about censored stuff through api believed it's Claude. Otherwise it doesn't know what model it is (or pretends to not know).