langgraph-state-management
LangGraph State Management
State Design Workflow
Follow this workflow when designing or modifying state for a LangGraph application:
- Identify data requirements — What data flows through the graph?
- Choose a schema pattern — Match the use case to a template
- Define reducers — Decide how concurrent updates merge
- Configure persistence — Select and set up a checkpointer
- Validate and test — Run schema validation and reducer tests
Quick Start
Python — Minimal Chat State
from langgraph.graph import StateGraph, START, END, MessagesState
from langchain_core.messages import AIMessage
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