LangGraph
Agent Frameworks (Developers)
- Build stateful, multi-agent apps as graphs
- Human-in-the-loop and durable execution
- Works with any LLM
- Open-source with a hosted platform
AI Agents & Automation (25)
25 free AI agent frameworks for developers and 0 more — pricing tier and real capabilities on every entry. No ads, no sponsored placement.
AllGeneral Autonomous AgentsWorkflow AutomationAgent Frameworks (Developers)Real-Time Voice AgentsBrowser & Computer-Use AgentsMCP EcosystemAgent Memory & RAG-as-a-Service
free
CrewAI
Agent Frameworks (Developers)
- Role-based multi-agent 'crews'
- Simple Python API for collaboration
- Tasks, tools and flows
- Open-source core
OpenAI Agents SDK
Agent Frameworks (Developers)
- Lightweight agent orchestration from OpenAI
- Agent handoffs, guardrails and tracing
- Tool and function calling built in
- Open-source, pay only for model usage
Microsoft AutoGen
Agent Frameworks (Developers)
- Multi-agent conversation framework
- Event-driven, async agent design
- Studio UI for prototyping
- Fully open-source
LlamaIndex
Agent Frameworks (Developers)
- Leading framework for RAG and data agents
- Connect LLMs to your documents & APIs
- Agentic document workflows
- Open-source with a hosted cloud
Google Agent Development Kit (ADK)
Agent Frameworks (Developers)
- Open-source Python/Java framework from Google for building multi-agent systems
- Native integration with Vertex AI Agent Engine and Gemini models
- Model-agnostic — works with non-Google LLMs via LiteLLM
Pydantic AI
Agent Frameworks (Developers)
- Type-safe Python agent framework from the Pydantic team, validated structured outputs
- Model-agnostic (OpenAI, Anthropic, Gemini, Groq, Mistral, local)
- Built-in dependency injection and streaming; pairs with Pydantic Logfire for observability
Mastra
Agent Frameworks (Developers)
- Open-source TypeScript framework (Apache 2.0) for agents, workflows and RAG
- Drops directly into existing React/Next.js apps or runs standalone
- Built-in workflow engine with suspend/resume and human-in-the-loop steps
Agno
Agent Frameworks (Developers)
- Open-source (Apache-2.0) Python framework, 41.7k GitHub stars
- AgentOS: FastAPI-based production runtime for deploying agents
- Control-plane UI for monitoring live agent systems across clouds
smolagents
Agent Frameworks (Developers)
- Extremely minimal open-source library (~1,000 lines) from Hugging Face
- CodeAgent paradigm: agents write actions as executable code, not JSON
- Model-agnostic and modality-agnostic (text, vision, audio) with sandboxed execution via E2B/Docker/Modal
AWS Strands Agents
Agent Frameworks (Developers)
- Open-source (6,800+ stars) Python and TypeScript SDK from AWS
- Steering handlers/hooks that catch agent mistakes before execution
- Native Bedrock and AWS AgentCore integration, plus any-LLM support
DSPy
Agent Frameworks (Developers)
- Open-source (MIT) framework from Stanford NLP, 37k+ GitHub stars
- Compiles/optimizes prompts automatically against metrics instead of manual prompt tuning
- Production use at Databricks, Shopify, Dropbox, AWS; Shopify reports ~550x cost reduction
- Unified open-source framework for building and orchestrating multi-agent systems in Python and .NET
- Successor merging Semantic Kernel and AutoGen ideas
- Graph workflows, memory and tool support
- Free, MIT-licensed
- Secure, fast runtime for executing untrusted AI-generated code
- SDKs and a self-hostable server
- Container and microVM isolation options
- Apache-licensed open source
- Agent framework built on Qwen 3+ with function calling, MCP and code interpreter
- Ships Browser Assistant and RAG examples
- Free and self-hostable
- Works with Qwen served locally or via DashScope
- Open-source framework for AI apps in JavaScript, Go, Dart and Python
- Built-in Developer UI for tracing and testing flows
- Model-agnostic plugins for Gemini, OpenAI, Anthropic, Ollama
- Free; deploy anywhere
- MIT-licensed Python and TypeScript SDKs exposing the agent loop that powers Claude Code
- Built-in tools for files, shell and MCP with custom tool support
- Bring an Anthropic API key; the SDK itself costs nothing
- MIT SDK for integrating LLMs into C#, Python and Java apps
- Plugins, planners and memory connectors
- Works with OpenAI, Azure and local models
- MIT-licensed framework of model, tool and retrieval integrations for agents
- Python and JavaScript versions
- Pairs with LangGraph and LangSmith (separate free tier)
- Batteries-included agent harness with planning, sub-agents and a virtual file system
- Built on LangGraph, model-agnostic
- Open source
- Apache-2.0 framework for context-engineered, production RAG and agent pipelines
- Modular components with retrievers, generators and tool calling
- Integrates most vector stores and model providers
- TypeScript toolkit for streaming text, tool calls and agents across many model providers
- React/Next/Vue/Svelte hooks for chat UIs
- Open source
- Open-source TypeScript agent framework with memory, tools and sub-agents
- VoltOps console for tracing (free tier)
- Provider-agnostic
- Open-source multi-agent framework focused on scaling agent societies and role-playing
- Data generation and simulation tooling
- Apache-licensed
- Framework for building and deploying stateful AI agents on Cloudflare Workers
- Built-in state, scheduling, WebSockets and MCP support
- SDK is open source; runs on Cloudflare's free tier to start
Agent Frameworks (Developers) — straight answers
What are the best free AI agent frameworks for developers?
Flocci AI Tools lists 25 AI agent frameworks for developers, ordered free tiers first: Agno, AWS Strands Agents, CAMEL, Claude Agent SDK and Cloudflare Agents SDK. All of them are free or have a free tier. Every entry states what it uniquely does, not a score.
Are there completely free AI agent frameworks for developers?
Yes — 23 of these are marked fully free with no paid plan attached: Agno, AWS Strands Agents, CAMEL, Claude Agent SDK and Cloudflare Agents SDK. The rest are freemium, trial or paid, and each row states which.
What should I look for in AI agent frameworks for developers?
Start with what you need to do: build your own multi-agent system in code. Then check the pricing tier, because "free" here means no paid plan at all while "freemium" means a free tier under paid plans. Every tool on this page lists both.
See the full list →Head-to-head comparisons
Agno vs AWS Strands AgentsAgno vs CAMELAgno vs Claude Agent SDKAgno vs Cloudflare Agents SDKAgno vs DSPyAWS Strands Agents vs CAMELAWS Strands Agents vs Claude Agent SDKAWS Strands Agents vs Cloudflare Agents SDK
Free alternatives
LangGraph alternativesCrewAI alternativesOpenAI Agents SDK alternativesMicrosoft AutoGen alternativesLlamaIndex alternativesGoogle Agent Development Kit (ADK) alternativesPydantic AI alternativesMastra alternatives
Looking for a ranked shortlist instead? See the best free AI agent frameworks for developers.