Chains with no inputs

[Omegastick]

If I'm not mistaken, right now, chains with no inputs aren't possible unless you override Chain.prep_inputs().

My use-case for this is chatbots with "cold-starts". The first call doesn't have an input, allowing the chatbot to start the conversation. Along the same lines, chains that include an environment (in the RL sense) for the agent to interact with, which wouldn't really make sense to require an 'input'.

If there's no reason this use-case shouldn't be handled, I can make a PR.

[hwchase17]

this use case should def be allowed! whats the error you're running into?

[dosubot[bot]]

Hi, @Omegastick! I'm here to help the LangChain team manage their backlog and I wanted to let you know that we are marking this issue as stale.

From what I understand, you opened an issue about the inability to create chains with no inputs in the current implementation. This feature would be useful for chatbots with "cold-starts" and for chains that include an environment for the agent to interact with. hwchase17 also commented on the issue, asking for more details about the error you are encountering.

Before we proceed, we would like to confirm if this issue is still relevant to the latest version of the LangChain repository. If it is, please let us know by commenting on the issue. Otherwise, feel free to close the issue yourself or it will be automatically closed in 7 days.

Thank you for your contribution to the LangChain project!

[Omegastick]

I think this has been implemented by someone else now. Closing.

[dosubot[bot]]

Thank you, @Omegastick, for closing the issue. We appreciate your contribution to the LangChain repository!