FixesNousResearch/hermes-agent#13848
Kimi's /coding endpoint speaks the Anthropic Messages protocol but has its
own thinking semantics: when thinking is enabled, Kimi validates message
history and requires every prior assistant tool-call message to carry
OpenAI-style reasoning_content.
The Anthropic path never populated that field, and
convert_messages_to_anthropic strips all Anthropic thinking blocks on
third-party endpoints — so the request failed with HTTP 400:
"thinking is enabled but reasoning_content is missing in assistant
tool call message at index N"
Now, when an assistant message contains tool_calls and a
reasoning_content string, we append a {"type": "thinking", ...} block
to the Anthropic content so Kimi can validate the history. This only
affects assistant messages with tool_calls + reasoning_content; plain
text assistant messages are unchanged.
2efb0eea21