Aperçu
LangGraph construit des workflows d'agent multi-étapes et stateful sous forme de graphes. Supporte le routage conditionnel, les points de contrôle human-in-the-loop, l'état persistant, le streaming et l'orchestration multi-agent. La conception basée sur des graphes permet un comportement d'agent complexe et contrôlable.
Installation
uv pip install langgraph
Graphe simple
from typing import TypedDict
from langgraph.graph import StateGraph, END
class AgentState(TypedDict):
messages: list
next_step: str
def research(state):
return {"messages": state["messages"], "next_step": "write"}
def write(state):
return {"messages": state["messages"], "next_step": "review"}
def review(state):
return {"messages": state["messages"], "next_step": "__end__"}
graph = StateGraph(AgentState)
graph.add_node("research", research)
graph.add_node("write", write)
graph.add_node("review", review)
graph.set_entry_point("research")
graph.add_edge("research", "write")
graph.add_conditional_edges("write", lambda s: s["next_step"])
graph.add_edge("review", END)
app = graph.compile()
result = app.invoke({"messages": [], "next_step": ""})