The best OpenAI Agents SDK alternatives
8 tools that do a similar job to OpenAI Agents SDK, 8 of them open source. Each entry says what it does and who it suits, so you can pick the one that fits instead of the most famous.
You're replacing
OpenAI Agents SDKA Python SDK for building AI agents that use tools, hand off tasks, and keep conversation history.
- 1
LangGraph
Open source · MIT · ★ 44.3k
A Python framework for building long-running agents that keep state and can resume after failures.
Best for: Python developers building multi-step AI agents that must survive failures or long waits; Teams that want fine-grained control over agent state and execution flow
- 2
CrewAI
Open source · MIT · ★ 60.4k
Python framework for building teams of role-playing AI agents that work together on tasks.
Best for: Python developers prototyping multi-agent workflows; Teams that want role-based agents collaborating on a task
- 3
LlamaIndex
Open source · MIT · ★ 52.8k
Python framework for building LLM apps that query your own documents and data.
Best for: Python developers building retrieval-augmented generation (RAG) apps over private documents; Teams wanting a modular toolkit where they can swap LLM, embedding and vector store providers
- 4
Semantic Kernel
Open source · MIT · ★ 28.7k
Open-source SDK for building AI agents and multi-agent apps in Python, .NET and Java.
Best for: Developers already using Azure OpenAI or OpenAI who want a structured SDK for agents; Teams working in .NET, Python or Java who want one framework across languages
- 5
Pydantic AI
Open source · MIT · ★ 21k
A typed Python SDK for building AI agents that work with many LLM providers.
Best for: Python developers building LLM-powered features that need structured, typed output; Teams that want to swap or fall back between model providers without rewriting code
- 6
PageIndex
Open source · MIT · ★ 40k
Lets an AI find answers in long documents by reading a table-of-contents-style tree, not vector search.
Best for: Developers building question-answering over long PDFs such as annual reports or manuals; Teams who want retrieved answers to be traceable to explicit sections of a document
- 7
CopilotKit
Open source · MIT · ★ 38.5k
A TypeScript toolkit for building chat and generative UI on top of AI agents in web, mobile, and chat apps.
Best for: Developers adding an AI assistant or agent interface to a React or Next.js app; Teams who want one agent backend to serve a web app, a mobile app, and Slack or Teams
- 8
Deep Agents
Open source · MIT · ★ 30.9k
An open-source Python agent harness for multi-step AI work, built on LangGraph.
Best for: Developers building AI agents that run multi-step tasks such as research and writing; Teams that want a working agent harness they can customize instead of building one from scratch
How we pick: tools in the same category that solve the same problem, projects that name each other as alternatives, and open-source projects that describe themselves as an alternative to OpenAI Agents SDK. We don't take payment for placement.