Best AI Agent Frameworks
Build custom AI agents from scratch with powerful open-source frameworks. Perfect for developers who need full control and customization.
AI agent frameworks are libraries and tools that provide the building blocks for creating custom agents. Instead of using a pre-built platform, you write code to orchestrate LLMs, manage memory, call tools, and handle errors. Frameworks like LangChain, LlamaIndex, and crewAI abstract away low-level details while giving you complete flexibility. This approach is ideal for developers building unique applications, researchers experimenting with agent architectures, or companies needing proprietary solutions.
Quick Picks
CrewAI
Open-source framework for orchestrating role-playing autonomous AI agents working together as a crew.
LangGraph
LangChain's graph-based framework for building stateful, cyclic agent workflows with loops and persistence.
AutoGen (Microsoft)
Microsoft's open-source framework for building conversational multi-agent systems with human feedback.
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CrewAI
Open-source framework for orchestrating role-playing autonomous AI agents working together as a crew.
AutoGen (Microsoft)
Microsoft's open-source framework for building conversational multi-agent systems with human feedback.
LangGraph
LangChain's graph-based framework for building stateful, cyclic agent workflows with loops and persistence.
AgentGPT
Browser-based autonomous AI agent that breaks down goals into tasks and executes them independently.
What AI Frameworks Provide
LLM Orchestration
Abstract interfaces for calling multiple LLM providers
Tool Management
Define and manage tools the agent can use
Memory Systems
Built-in memory types: conversation, semantic, episodic
Agent Templates
Pre-built agent patterns and workflows
Evaluation Tools
Test and benchmark agent performance
Open Source
Full transparency, community contributions, no vendor lock-in
Full Comparison
| # | AI Agent | Rating | Ease of Use | Performance | Free Tier | Price | Action |
|---|---|---|---|---|---|---|---|
| 1 | CrewAIEditor's Choice frameworks • 5 models | 4.5 | 4.3 | 4.6 | Free | ||
| 2 | AutoGen (Microsoft) frameworks • 4 models | 4.3 | 4.0 | 4.4 | Free | ||
| 3 | LangGraphEditor's Choice frameworks • 4 models | 4.4 | 4.2 | 4.5 | Free | ||
| 4 | AgentGPT frameworks • 2 models | 4.0 | 4.8 | 3.8 | Free |
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