LangGraph Studio Troubleshooting¶

Safari Connection Issues¶

Safari blocks plain-HTTP traffic on localhost. When running Studio with langgraph dev, you may see "Failed to load assistants" errors.

Solution 1: Use Cloudflare Tunnel¶

PythonJS

pip install -U langgraph-cli>=0.2.6
langgraph dev --tunnel

# Requires @langchain/langgraph-cli>=0.0.26
npx @langchain/langgraph-cli dev

The command outputs a URL in this format:

https://smith.langchain.com/studio/?baseUrl=https://hamilton-praise-heart-costumes.trycloudflare.com

Use this URL in Safari to load Studio. Here, the baseUrl parameter specifies your agent server endpoint.

Solution 2: Use Chromium Browser¶

Chrome and other Chromium browsers allow HTTP on localhost. Use langgraph dev without additional configuration.

Brave Connection Issues¶

Brave blocks plain-HTTP traffic on localhost when Brave Shields are enabled. When running Studio with langgraph dev, you may see "Failed to load assistants" errors.

Solution 1: Disable Brave Shields¶

Disable Brave Shields for LangSmith using the Brave icon in the URL bar.

Brave Shields

Solution 2: Use Cloudflare Tunnel¶

PythonJS

pip install -U langgraph-cli>=0.2.6
langgraph dev --tunnel

# Requires @langchain/langgraph-cli>=0.0.26
npx @langchain/langgraph-cli dev

The command outputs a URL in this format:

https://smith.langchain.com/studio/?baseUrl=https://hamilton-praise-heart-costumes.trycloudflare.com

Use this URL in Brave to load Studio. Here, the baseUrl parameter specifies your agent server endpoint.

Graph Edge Issues¶

Undefined conditional edges may show unexpected connections in your graph. This is because without proper definition, LangGraph Studio assumes the conditional edge could access all other nodes. To address this, explicitly define the routing paths using one of these methods:

Solution 1: Path Map¶

Define a mapping between router outputs and target nodes:

PythonJavascript

graph.add_conditional_edges("node_a", routing_function, {True: "node_b", False: "node_c"})

graph.addConditionalEdges("node_a", routingFunction, { true: "node_b", false: "node_c" });

Solution 2: Router Type Definition (Python)¶

Specify possible routing destinations using Python's Literal type:

def routing_function(state: GraphState) -> Literal["node_b","node_c"]:
    if state['some_condition'] == True:
        return "node_b"
    else:
        return "node_c"