"Error in on_chain_start callback: 'name'" warning for tutorial "How to add Memory to an LLMChain"

[labdmitriy]

System Info

LangChain version: 0.0.198 Platform: Ubuntu 20.04 LTS Python version: 3.10.4

Who can help?

No response

Information

• [X] The official example notebooks/scripts
• [ ] My own modified scripts

Related Components

• [ ] LLMs/Chat Models
• [ ] Embedding Models
• [ ] Prompts / Prompt Templates / Prompt Selectors
• [ ] Output Parsers
• [ ] Document Loaders
• [ ] Vector Stores / Retrievers
• [ ] Memory
• [ ] Agents / Agent Executors
• [ ] Tools / Toolkits
• [X] Chains
• [ ] Callbacks/Tracing
• [ ] Async

Reproduction

1. Reproduce tutorial How to add Memory to an LLMChain
2. Get the same warning for each invocation of llm_chain.predict(): Error in on_chain_start callback: 'name'
3. The same warning will be for the following different configurations (only difference from original code is specified): 3.1.llm = ChatOpenAI(temperature=0) 3.2 chain = ConversationChain( memory=memory, verbose=True, prompt=prompt_template, llm=llm, input_key='human_input' ) 3.3 memory = ConversationBufferMemory(memory_key='chat_history', return_messages=True)

Expected behavior

There will be no such warnings (or the actions which resolved it must be specified in warning and/or in documentation).

[tiratano]

Same problem. Hope not to see any red warning messages either.

[labdmitriy]

I found that the first version that has this warning is the latest one (0.0.198), before that there were no such warnings.

[zzz2016]

same issue

[PierreSylvain]

This occurs only when verbose is set to True

[Felliks]

Same problem when use AgentType.STRUCTURED_CHAT_ZERO_SHOT_REACT_DESCRIPTION

[lidh15]

I use verbose=True and AgentType.STRUCTURED_CHAT_ZERO_SHOT_REACT_DESCRIPTION simply because it is demoed in the doc and in fact, I don't know what is happening behind.

[rajaniesh]

same issue here as well

[tiratano]

Since updating to 0.0.200, I have not had any warnings.

[vowelparrot]

This was an issue with the stdout callback handler that was fixed in v0.0.200

[AndreuCodina]

It still occurs with verbose=True

langchain version 0.0.207

[dyllanwli]

add langchain.debug = True when you want to use verbose=True. It can temporally solve the problem, that replace the StdOutCallbackHandler to ConsoleCallbackHandler.

[vowelparrot]

I could review a PR fixing StdOutCallbackHandler if that is still broken

[CloudDragonGong]

How should I update? This seems to be the latest. My pip cannot be updated anymore. Can you provide guidance? thanks

[apoorv-nag]

I am trying to run the main.py code given for langchain app in the vocode github but the agent is not working well with outbound number.