LangChain
LangChain is the most widely adopted framework for building applications powered by large language models. It provides a composable set of abstractions that let you connect LLMs to tools, data sources, and multi-step reasoning pipelines with minimal boilerplate.
LangGraph Deep Dive
LangGraph is a framework for building stateful, multi-actor agent applications as directed graphs. Built on top of LangChain primitives, it gives you explicit control over agent control flow, state management, and human-in-the-loop interactions that the older AgentExecutor pattern cannot provide.
CrewAI
CrewAI is a multi-agent orchestration framework built around the metaphor of a team ("crew") of specialized AI agents collaborating to accomplish complex tasks. Its role-based design makes it intuitive to set up and reason about, especially for workflows that mirror real-world team structures.
AutoGen
AutoGen, developed by Microsoft Research, is a framework for building multi-agent systems through conversable agents that communicate via message passing. Its core design principle is that complex tasks can be solved by having specialized agents engage in structured conversations, much like a team collaborating in a group chat.
Semantic Kernel
Semantic Kernel (SK) is Microsoft's open-source SDK for integrating large language models into applications. Originally designed for .NET, it now has full Python and Java SDKs. Semantic Kernel differentiates itself with a plugin-centric architecture and tight integration with the Azure ecosystem, making it a strong choice for enterprise applications.
LlamaIndex Agents
LlamaIndex (formerly GPT Index) started as a data framework for connecting LLMs to external data sources. It has since evolved into a full agent framework with a distinctive strength: treating data retrieval pipelines as first-class agent tools. If your agent's primary job is to query, synthesize, and reason over complex data sources, LlamaIndex agents are purpose-built for that workflow.
OpenAI Assistants API
The OpenAI Assistants API is a managed, stateful agent runtime provided directly by OpenAI. Unlike the stateless Chat Completions API, the Assistants API handles conversation state, tool execution, and file management on OpenAI's servers. This makes it the fastest path to a production agent if you are committed to the OpenAI ecosystem.
Framework Comparison
Choosing the right agentic AI framework is one of the most consequential early decisions in a project. Each framework encodes a set of opinions about how agents should be built, and those opinions have downstream effects on development velocity, debugging, scalability, and maintenance. This page provides a structured comparison to help you make an informed choice.