conditional edges to every node in graph when using tools_condition from langgraph.prebuild

[rugrill]

Hi there,

I'm using the tools_condition from langgraph.prebuild to decide in a conditional edge whether to call a tool or go to the end node. So I initialised a ToolNode, also from the langgraph.prebuild library. However, the source node of the conditional node has a conditional node not only to the ToolNode as expected, but also to every other node in the graph.

In Langgraph Studio or a Mermaid diagram this looks like this

I'm expecting a graph more like this:

Apart from the overhead of the edges, the graph works fine and like indendet. I'm just curious how to get a cleaner graph.

How does the prebuild tools_condition function work in detail? From my understanding the function should only route to tool nodes or the end node.

I've also worked with a dictionary to map to the nodes I want, then I get key errors for the tools and end nodes.
graph.add_conditional_edges("node_a", routing_function, {True: "tools", False: "__end__"})}

This is my graph in code:

from langgraph.graph import START, StateGraph, MessagesState, END
from langgraph.prebuilt import tools_condition, ToolNode


builder = StateGraph(st.State)


builder.add_node("query_word", nd.query_word)
builder.add_node("error_code", nd.error_code)
builder.add_node("retrieve_hb", nd.retrieve_hb)
builder.add_node("retrieve_sr", nd.retrieve_sr)
builder.add_node("writer_assistant", nd.writer_assistant)
builder.add_node("tools", ToolNode([create_instructions]))


builder.add_edge(START, "query_word")
builder.add_edge(START, "error_code")
builder.add_edge("query_word", "retrieve_hb")
builder.add_edge("error_code", "retrieve_sr")
builder.add_edge(["retrieve_hb", "retrieve_sr"], "writer_assistant")
builder.add_conditional_edges("writer_assistant", tools_condition)
builder.add_edge("tools", "writer_assistant")

graph = builder.compile()

The versions I'm using:
langchain==0.3.7
langchain-community==0.3.7
langchain-core==0.3.18
langgraph==0.2.48
langgraph-checkpoint==2.0.4
langgraph-sdk==0.1.36
langsmith==0.1.143

Thank you!

[vbarda]

Thanks for reporting -- found the issue, will fix up in the next patch release. In the meantime, you can fix it by doing this:

builder.add_conditional_edges("writer_assistant", tools_condition, path_map=["tools", "__end__"])

[dsantiago]

This path_map solves for now the issue... Also got some spaghetti like graphs here resultant from have logic conditional_edges...

[muskan2212]

@rugrill use like this, it should work
builder.add_conditional_edges(

"<your parent node>", 
"<conditional node>", 
{    
    "<conditional response 1>": "<required node 1>",  
    "<conditional response 2>": "<required node 2>",
},