config with thread_id error

[LizhongLiu-cims]

I try to run code here: examples/langgraph-python/langgraph_e2b_python/code_interpreter_tool.py

All my code is same as the example, expect that I added the memorysaver to enable the llm have chat memory for constant chat experience.

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workflow = MessageGraph() workflow.add_node("agent", llm.bind_tools(tools)) workflow.add_node("action", lambda x: execute_tools(x, tool_map))

Conditional agent -> action OR agent -> END

workflow.add_conditional_edges( "agent", should_continue, )

Always transition action -> agent

workflow.add_edge("action", "agent")

workflow.set_entry_point("agent") memory = MemorySaver() app = workflow.compile(checkpointer = memory)

4. Invoke the app

config = {"configurable": {"thread_id": str(uuid.uuid4())}} result = app.invoke(input=("user", "please generate a random line plots"), config = config)

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I got error message below when try to add config argument:

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venv\lib\site-packages\langgraph\serde\jsonplus.py:72, in JsonPlusSerializer._default(self, obj) 68 return self._encode_constructor_args( 69 obj.class, kwargs={"node": obj.node, "arg": obj.arg} 70 ) 71 else: ---> 72 raise TypeError( 73 f"Object of type {obj.class.name} is not JSON serializable" 74 )

TypeError: Object of type Result is not JSON serializable

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I suppose the error comes due to change of message format that can not be json.dump(), is there any quick way to fix this? like some parser function maybe?

[mlejva]

Hi @LizhongLiu-cims, yes this looks like a JSON format problem. Sometimes the model ignores the required JSON schema they should be producing. This could be related

[LizhongLiu-cims]

Hi @mlejva, in that way, if I want to add memory as checkpointer to save the history, do I need to rewrite my own memory function instead of using MemorySaver() from langgraph.checkpoint? If that way, could you please provide an demo example to follow? Thanks!