I don't know about real successful. Since you mentioned Langchain, you could look at https://www.langchain.com/dcode https://www.langchain.com/dcode which is a

I don't know about real successful. Since you mentioned Langchain, you could look at https://www.langchain.com/dcode https://www.langchain.com/dcode which is a CLI harness build off Langchain deep agents.