Best AI Agent Frameworks (2026)
Frameworks, SDKs and harnesses developers use to build their own AI agents. Below are the top 20 of 133 matching tools in the AgentScout directory, ranked.
Updated
How we ranked: Ranked by GitHub stars as recorded on each AgentScout listing (link checks 2026-10-21). Tools without a tracked public repo come after, in alphabetical order. Stars measure developer popularity, not quality or fit for your job, so read each listing before you choose. No paid placements.
Quick comparison Top 10 of 20 listed below. Pricing as the maker states it; blank means we don't have it.
| Tool | Pricing | Best for | Open source |
|---|---|---|---|
 Hermes Agent (Nous Research) | Open source | Build an agent | Yes |
 DeepSeek Harness | Open source | Build an agent | Yes |
 AutoGPT | Source-available + cloud | Build an agent | Source-available |
 Ruflo | Open source | Build multi-agent systems | Yes |
 MetaGPT | Open source | Build an agent | Yes |
 AutoGen | Open source | Build multi-agent systems | Yes |
 CrewAI | Open source + cloud | Build multi-agent systems | Yes |
 PrivateGPT | Open source | Build an agent | Yes |
 LlamaIndex | Open source + cloud | Build an agent | Yes |
 LangGraph | Open source | Build an agent | Yes |
1. Hermes Agent (Nous Research)
Open-source agent harness; v0.21.7 stable shipped Oct 12, v0.22.0 RCs Oct 13-14.
Pricing (as stated): Open source · Active, frequent releases
2. DeepSeek Harness
DeepSeek's open-source agent harness with a local web UI, built so that every tool, model and scheduled task is a swappable plugin; still a developer preview.
Pricing (as stated): Open source · Mature
3. AutoGPT
One of the first autonomous agent projects, now a platform for building, deploying and running continuous AI agents that automate workflows.
Pricing (as stated): Source-available + cloud · Mature
4. Ruflo
Open-source multi-agent meta-harness for Claude Code, Codex, and MCP clients; Oct 13 release adds Mods (mission workflows) and a single control plane with human approval.
Pricing (as stated): Open source (MIT); model costs still apply · Active
5. MetaGPT
Multi-agent framework that assigns roles like product manager and engineer to LLM agents to build software.
Pricing (as stated): Open source · Mature
6. AutoGen
Microsoft's framework for multi-agent conversations, now archived and no longer maintained; Microsoft points new users to Microsoft Agent Framework.
Pricing (as stated): Open source · Archived (no longer maintained)
7. CrewAI
Framework for role-based multi-agent crews.
Pricing (as stated): Open source + paid cloud · Mature
8. PrivateGPT
Open-source API layer that turns local models into private AI applications, with RAG, tools, skills, MCP and text-to-SQL on any OpenAI-compatible server.
Pricing (as stated): Open source · Mature
9. LlamaIndex
Framework for agents over your data (RAG, document agents).
Pricing (as stated): Open source + paid cloud · Mature
10. LangGraph
Framework for stateful, graph-based agent workflows.
Pricing (as stated): Open source · Mature
11. Agno
Python framework and runtime for building, running and managing multi-agent systems with memory, knowledge and tools.
Pricing (as stated): Open source + cloud · Mature
12. OpenHuman
Lightweight open-source agent harness designed to run many agents cheaply on small servers.
Pricing (as stated): Open source · Mature
13. AstrBot
Open-source agent chatbot platform and framework that connects LLMs, plugins and tools to mainstream messaging apps for assistants, support bots and knowledge bases.
Pricing (as stated): Open source · Mature
14. DSPy
Stanford framework for programming rather than prompting language models, with optimizers that tune prompts and weights for RAG pipelines and agent loops.
Pricing (as stated): Open source · Mature
15. CopilotKit
Frontend stack for putting agents and generative UI into React and other apps, from the makers of the AG-UI protocol.
Pricing (as stated): Open source + cloud · Mature
16. ChatDev
Zero-code multi-agent platform from OpenBMB, grown from a software-development agent company into a general multi-agent orchestration system.
Pricing (as stated): Open source · Mature
17. AgentScope
Framework for building and running transparent multi-agent applications with visual debugging.
Pricing (as stated): Open source · Mature
18. Orkes
Orchestration platform built on Conductor for durable workflows and AI agents.
Pricing (as stated): Open source + cloud · Mature
19. LangChain Deep Agents
Library for long-running agents with subagents and skills; 0.7.23 (Oct 7) adds pinned_skills.
Pricing (as stated): Open source · Active
20. OpenAI Agents SDK (Python)
OpenAI's Python SDK for building multi-agent workflows; v0.23.0/0.23.1 released Oct 1-2.
Pricing (as stated): Open source · Mature, official SDK
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Related: AI agents for building AI agents · Multi-agent systems
Related searches: Open-source AI agent frameworks · Python AI agent frameworks · TypeScript and JavaScript AI agent frameworks · Multi-agent frameworks
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Facts come from our directory listings; pricing is as each maker states it and GitHub stars are as recorded on each listing. Check official sites before you choose.