Mermaid.ink has been known to timeout when rendering graphs with very short node names like "A", particularly in Jupyter notebooks using langgraph. This appears to be a bug or parsing edge case in Mermaid.ink’s backend. Longer node names such as "start_node" or "chatbot" tend to work reliably and avoid the issue. Interestingly, the same Mermaid code usually renders fine in the Mermaid Live Editor, suggesting the problem is specific to Mermaid.ink’s API or langgraph’s integration. Workarounds include using longer node names, switching to Pyppeteer for local rendering, or running a local Mermaid server via Docker.