Mark internal property as `private` for cleaner autocompletion.

### Describe the feature

Could we hide (marked as `private`) these internal properties so that only the public API appears during autocompletion?

<img width="824" alt="Image" src="https://github.com/user-attachments/assets/d131ec56-472d-418c-b270-9e89212dc268" />

### Additional information

- [x] Would you be willing to help implement this feature?