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Raunak ALI
Raunak ALI

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LangGraph vs. Chains: Building Smarter AI Workflows With State, Branching, and Memory

Introduction: From Foundations to Real-World Agent Workflows

If you’ve followed along with the first series Article 1 :Series , you’ve built a solid foundation in Generative AI, the inner workings of LLMs, and how frameworks like LangChain empower you to chain models and tools in practical applications.

We wrapped up by getting hands-on with Google Gemini and DuckDuckGo, showcasing how to connect language models to real-time web search for richer, up-to-date insights.

But this is only the beginning.

What comes next?

The real power of modern AI frameworks lies not just in connecting LLMs to tools, but in designing autonomous, agentic workflows, ie systems that can reason, act, and learn with minimal supervision. This is where we move from simple pipelines to intelligent agents capable of carrying out sophisticated tasks.

In this new article series, we’ll chart a path:

  • From basic LLM interactions to the architecture behind single-agent workflows.

  • From writing prompts and chaining APIs, to building autonomous agents using LangGraph.

  • We’ll explore not only how these agents think , but also how to structure, deploy, and scale them, bringing theory into actionable code.

  • Whether you’re aiming to automate research, streamline business processes, or create next-gen AI products, this journey will take you from the core ideas to hands-on implementation.


1. What is LangGraph?

At its core, LangGraph is a framework built on top of LangChain that allows you to design stateful, graph-based workflows for LLM-powered systems. Think of it as moving from a straight line to a map of possible paths.

Why This Matters

Most of us start with simple LLM calls:

  • You send a prompt → the model replies.

That works for toy problems, but breaks quickly when you need multi-step reasoning, memory, or dynamic decisions.

LangChain improved on this by giving us LLM chains:

  • A sequence of steps where one output becomes the input to the next.
  • Great for linear workflows (summarize → translate → format).
  • But still stateless and rigid — if you need branching or state tracking, it becomes clunky.

Enter LangGraph:

  • Here, your workflow is expressed as a graph:
    • Nodes = steps (e.g., call an LLM, fetch from a DB, apply logic).
    • Edges = the possible paths between steps.
    • State = context that persists across nodes.

This means agents don’t just follow a checklist; they can branch, revisit steps, remember context, and adapt.

In other words:

  • Chains = pipelines.
  • Graphs = decision systems.

2. Why LangGraph is a Step Towards Agentic AI

So why is this shift so important? Because it’s the foundation for Agentic AI.

Agents are more than LLMs. They’re systems that can:

  • Reason across steps (not just one-off answers).
  • Use tools (search engines, databases, APIs).
  • Maintain memory (short-term context + long-term knowledge).
  • Adapt dynamically (change course depending on inputs).

LangGraph gives you the scaffolding to build these systems. Instead of relying on “prompt magic” or fragile chains, you now have a way to:

  • Break tasks into smaller sub-steps.
  • Manage state and memory across interactions.
  • Introduce branching logic (if this, then that).
  • Build persistent workflows that survive beyond a single request.

This is what makes LangGraph a real step forward: it moves us closer to building AI that behaves like autonomous agents, capable of reasoning, acting, and learning — rather than just predicting the next word.


Up next in Understanding Core Concepts of LangGraph (Deep Dive), we’ll dive into the core building blocks that make LangGraph tick: Nodes, Edges, and State. If you think of this chapter as the “why,” this next part is the “how”, a closer look at the execution units, the pathways between them, and the memory that makes workflows adaptive and alive.


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