But then again, the identity could also have slipped into the model from other sources during pretraining. The internet is full of "I am Claude": https://grep.app/search?q=i+am+claude and variants https://grep.app/search?q=i%27m+claude
Either way, there's probably no significant portion of Mythos/Fable or Sol in there as OP has stated.
When prefaced with "I am Claude", Kimi K3 prefers to generate API-specific Anthropic model identifiers, unlike other models Qwen, GPT, or even Claude itself. These exact identifiers appear in Claude API metadata, and are stripped out of Claude web chats.
While other models produce human-readable names like "Opus 4.5" or "Sonnet 4", Kimi K3 produces exact API model identifier like "claude-opus-4-5-20251101" or "claude-sonnet-4-20250514".
Which is extremely unusual. Web chats only contain the human-readable model name. Other models don't do this. So where did K3 get this data?
We can conclude, with high confidence, that:
1) K3 was trained on raw Claude API calls/metadata.
2) Claude API metadata was trained on in additional to standard web data.
The exact model identifiers appear extremely frequently in code on GitHub.
https://grep.app/search?q=claude-opus-4-5-20251101
https://grep.app/search?q=claude-sonnet-4-20250514
They also appear elsewhere on the internet:
https://trends.google.com/trends/explore?q=claude-opus-4-5-2...