Most developers pick the wrong AI agent framework. Not because they're bad developers, but because they ask the wrong question: "Which framework is best?" The right question is: "Which framework fits my specific use case?"
Let's cut through the noise. Here are 9 frameworks, each with a clear purpose, and a decision tree to help you choose.
The 9 Frameworks, Explained
LangChain
Python/JS framework for LLM-powered agents
Tool Calling
Agent Loops
Reasoning
The original gangster of AI frameworks. LangChain set the standard for building LLM-powered agents with its composable chains, tool integrations, and reasoning loops. If you're new to agents, start here.
LangGraph
State-machine / graph framework built on LangChain
State Machines
Branching
Loops & Retries
When you need absolute control over multi-step workflows. LangGraph uses a finite state machine approach that lets you define exactly how your agent moves between states, handles errors, and branches on conditions.
AutoGen
Microsoft's multi-agent framework
Agent Chats
Human-in-Loop
Research-Backed
Microsoft's research-backed approach to multi-agent systems. Agents talk to each other, collaborate on complex tasks, and can bring humans into the loop when needed. Production-ready for enterprise scenarios.
CrewAI
Role-based multi-agent framework
Clear Roles
Defined Goals
Orchestration
Think of it as your AI team. Each agent has a role (researcher, writer, reviewer), clear goals, and responsibilities. The mental model is intuitive: build a team, delegate tasks, get results.
LlamaIndex
Data + agent framework for LLM applications
Strong RAG
Structured Data
Agent Ready
The data person's choice. If your agent's superpower is accessing and synthesizing external knowledge, LlamaIndex offers the most mature toolkit for data ingestion, indexing, and retrieval.
Semantic Kernel
Microsoft's SDK for AI orchestration
Plugin System
Prompts + Tools
Memory
Microsoft's enterprise SDK with a clean plugin architecture. Combines prompts, tools, and memory seamlessly. If you're in the Microsoft ecosystem and need production-grade agents, this is your choice.
Haystack
Open-source framework for LLM pipelines
Modular
Strong Search
Python-First
The search specialist. Haystack's modular architecture makes it perfect for building search-based applications. Strong RAG support, Python-first design, and enterprise-ready features.
Google ADK
Open-source Agent Development Kit
Workflow Agents
Multi-Language
Built-in Streaming
Google's open-source framework for building production AI agents. Supports Python, TypeScript, Go, and Java. Model-agnostic with LiteLLM integration for 40+ providers. Workflow agents (Sequential, Parallel, Loop) for predictable pipelines or LLM-driven dynamic routing.
Mastra
TypeScript AI framework from the Gatsby team
40+ Models
Built-in Evals
Local Playground
From the team behind Gatsby, Mastra is built on Vercel's AI SDK for TypeScript developers. All-in-one framework with agents, workflows (graph-based), RAG, memory, and MCP support. Integrates with React, Next.js, and Node.js.
Quick Reference Table
Framework Comparison at a Glance
Choose based on your primary use case
| Framework | Type | Best For | Superpower |
|---|---|---|---|
| LangChain | General | RAG, tool-based agents | Composability |
| LangGraph | Control | Complex multi-step workflows | State machines |
| AutoGen | Multi-Agent | Collaborative agents | Human-in-the-loop |
| CrewAI | Team | Task delegation | Role-based design |
| LlamaIndex | RAG | Knowledge-driven agents | Data access |
| Semantic Kernel | Enterprise | Production agents | Plugin system |
| Haystack | Search | Search-based apps | Modular architecture |
| Google ADK | Open Source | Multi-language, workflow agents | Sequential/Parallel/Loop |
| Mastra | TypeScript | Modern web stack | Built on Vercel AI SDK |
The "right" framework isn't a singular choice. It's the one that matches your use case, tech stack, and control requirements.
Katonic: Deploy Any Framework, Zero Lock-in
Here's the thing: choosing a framework is just the beginning. Getting it to production is where most teams struggle. That's why we built Katonic to support all of these frameworks natively.
Full-Stack Agent Platform
Brain + Body + Guardrails on your infrastructure
Katonic's platform doesn't force you into a single framework. Bring your LangGraph agents, your CrewAI teams, your AutoGen conversations. We handle the deployment, UI, and governance so you can focus on building.
Framework Agnostic
Deploy agents built with any framework. No vendor lock-in.
Generative UI
Auto-generated frontends for your agents. No frontend code required.
Sovereign Deployment
On-premises, private cloud, or air-gapped. Your data never leaves.
The Bottom Line
Stop asking "which framework is best." Start asking "which framework fits my use case." Here's the cheat sheet:
- Starting out? → LangChain
- Need control? → LangGraph
- Multi-agent collaboration? → AutoGen or CrewAI
- Knowledge-driven? → LlamaIndex
- Microsoft ecosystem? → Semantic Kernel
- Search specialist? → Haystack
- Multi-language / workflow agents? → Google ADK
- TypeScript / modern web? → Mastra
And when you're ready to go to production? Katonic deploys them all.