December 2025 focused on clarifying GenerationConfig usage for max_new_tokens and its relationship to max_length in the Transformers library. Delivered a targeted feature: GenerationConfig Usage Documentation that clarifies token generation control and backward compatibility, alongside docstring updates and related code/doc changes. Specifically, the work moved the max_new_tokens recommendation into the GenerationConfig docstring, updated configuration_utils.py for clearer token semantics, and performed docs cleanups in generation guides (text_generation.md). While no major bugs were closed this month, the documentation improvements reduce user confusion and lower integration risk, enabling safer adoption of text generation features across downstream applications. Technologies exercised include Python, API/docs documentation practices, and maintenance workflows, with cross-team contributions documented.