langgraph 0.1.12

Summary of Changes

• Improved the ToolNode prebuilt component to ensure consistent string output from tools by automatically converting non-string returns to JSON or string representations #1114

Detailed Changes

langgraph.prebuilt.tool_node.ToolNode

• Added new str_output utility function that intelligently converts any output to a string format #1114
• Modified both sync (_run_one) and async (_arun_one) methods to ensure the content of returned ToolMessage is consistently a string #1114
• Added JSON serialization for structured outputs, with fallback to string representation for objects that can't be serialized to JSON #1114