January 2026: LangChain Newsletter

LangChain's January newsletter announces several updates, including the general availability of the LangSmith Agent Builder for creating agents with natural language. The release also features side-by-side LLM experiment comparisons to better identify regressions and improvements. A key conceptual point is the inseparability of tracing and testing for AI agents, emphasizing that production traces should directly power evaluations. New resources include an Agent Builder Academy course and a relaunched Chat LangChain site for documentation and support.