Langgraph is not a no-code tool for visual programming, it's an implementation of the Pregel algorithm for execution of cyclical computation graphs (ie not DAGs)
Honestly I'm happy to be proven wrong about the usefulness of it.
I've used langsmith and found it quite useful. I think I was just so jaded by my bad experience with Langchain, that I'm immediately skeptical of other "lang" products.
That being said, it's not doing that much. And you still end up having to use some of langchain's abstractions. If this current "make a cyclical graph of LLM agents that send messages to each other" thing has any staying power than I imagine we'll see a more robust option soon. Personally I'd love a way to build agent graphs in a strongly typed language with first class concurrency.