Beyond Linear Chains

LangChain agents follow linear paths: receive input → plan → use tools → respond. But real-world workflows need loops, branches, and state. That's where LangGraph comes in.

LangGraph extends LangChain with stateful, cyclic graphs—allowing agents to retry failed tools, route to specialized sub-agents, pause for human approval, and maintain complex workflows across multiple steps.

Interactive: Linear vs Graph Workflow

Sequential Execution (No Cycles):

User Input

Process

Response

❌ Cannot go back, branch, or loop

🎯 Why LangGraph?

🔄

Cycles & Loops

Retry failed tool calls, iteratively refine outputs, or loop until condition met.

🌳

Conditional Branching

Route to different nodes based on state, user input, or tool results.

🧠

Persistent State

Maintain conversation history, intermediate results, and context across steps.

👤

Human-in-the-Loop

Pause execution for human approval before critical actions (e.g., sending emails, making purchases).

💡 Real-World Use Cases

•

Multi-Step Research: Agent searches web, analyzes results, decides if more info needed, loops back to search again.

•

Customer Support Bot: Routes to FAQ agent, escalates to human if unresolved, returns to agent after human input.

•

Code Generation: Writes code, runs tests, fixes errors in loop until tests pass, then returns final code.

LangGraph for Workflows

Your Progress