bump core and update tool definition (#4)

Author: vbarda

langgraph_swarm/handoff.py

@@ -1,7 +1,7 @@
 import re
 
 from langchain_core.messages import ToolMessage
-from langchain_core.tools import BaseTool, InjectedToolCallId, StructuredTool
+from langchain_core.tools import BaseTool, InjectedToolCallId, tool
 from langgraph.graph.state import CompiledStateGraph
 from langgraph.prebuilt import ToolNode
 from langgraph.types import Command
@@ -32,6 +32,7 @@ def create_handoff_tool(*, agent_name: str, description: str | None = None) -> B
     if description is None:
         description = f"Ask agent '{agent_name}' for help"
 
+    @tool(name, description=description)
     def handoff_to_agent(
         tool_call_id: Annotated[str, InjectedToolCallId],
     ):
@@ -46,13 +47,8 @@ def handoff_to_agent(
             update={"messages": [tool_message], "active_agent": agent_name},
         )
 
-    handoff_tool = StructuredTool.from_function(
-        name=name,
-        description=description,
-        func=handoff_to_agent,
-        metadata={METADATA_KEY_HANDOFF_DESTINATION: agent_name},
-    )
-    return handoff_tool
+    handoff_to_agent.metadata = {METADATA_KEY_HANDOFF_DESTINATION: agent_name}
+    return handoff_to_agent
 
 
 def get_handoff_destinations(agent: CompiledStateGraph, tool_node_name: str = "tools") -> list[str]: