langgraph 0.3.8

Summary of Changes

• Enhanced handling of Pydantic models in StateGraph nodes by only sending state updates for fields that differ from their default values, rather than fields that were explicitly set by users #3783

Detailed Changes

langgraph.graph.state.StateGraph

• Improved how Pydantic model fields are handled when returned from node functions #3783
  • Changed from only updating values for keys explicitly set by users to only updating values that differ from default values
  • This provides more intuitive behavior when working with Pydantic models that have default values
  • Handles both Pydantic v1 and v2 correctly by examining model fields and their defaults