---
features:
  - |
    Added `ReasoningContent` as a new content part to the `ChatMessage` dataclass. This allows storing model
    reasoning text and additional metadata in assistant messages.
    Assistant messages can now include reasoning content using the `reasoning` parameter in
    `ChatMessage.from_assistant()`.
    We will progressively update the implementations for Chat Generators with LLMs that support reasoning to use this
    new content part.
