Devtoolwatch BoardBest AI agent frameworks, ranked by real usage
44 AI agent frameworks ranked by new GitHub stars and npm and PyPI download growth, the week of Oct 25–31, 2026. Updated every Monday.
| Rank | Tool | Stars | Downloads/wk | vs 4-wk avg |
|---|---|---|---|---|
| #1 | Harness²Harness² is a Python framework from Google Research for recursive agent harnessing, refining an agent's prompts, tools, memory and… | 21.7k | – | – |
| #2 | HyperFramesHyperFrames is an open-source framework that turns HTML, CSS, media, and seekable animations into deterministic MP4 videos, built for AI… | 76.6k | 1.5M | +67% |
| #3 | AgentScopeAgentScope is a Python agent framework with an SDK for building ReAct agents and an agent service backend with a web UI. | 35k | 51.4k | +38% |
| #4 | AG-UIAG-UI is an open, event-based protocol that standardizes how AI agents connect to user-facing frontend applications. | 16.9k | 4.6M | +45% |
| #5 | LangGraphLangGraph is a low-level orchestration framework and runtime for building, managing, and deploying long-running, stateful agents in… | 44.2k | 18.5M | +10% |
| #6 | BifrostOpen-source, high-performance AI gateway that works as your LLM gateway, MCP gateway and agent gateway. One OpenAI-compatible API for… | 9.3k | – | – |
| #7 | assistant-uiassistant-ui is an open-source TypeScript/React library of composable primitives and runtimes for building AI chat interfaces in your app. | 12.9k | 2.8M | +16% |
| #8 | MastraMastra is a TypeScript framework for building AI-powered applications and agents, with workflows, memory, model routing, MCP servers,… | 29.2k | 3.1M | +22% |
| #9 | Deep AgentsDeep Agents is an open source, opinionated agent harness from LangChain, built on LangGraph, with sub-agents, filesystem, context… | 30.8k | 2.5M | +13% |
| #10 | Vercel AI SDKVercel AI SDK is a provider-agnostic TypeScript toolkit for building AI-powered applications and agents with frameworks like Next.js,… | 27.7k | 42.6M | +17% |
| #11 | OpenAI Agents SDKOpenAI Agents SDK is a Python framework from OpenAI for building multi-agent workflows with tools, handoffs, guardrails, sessions and… | 30.4k | 6.9M | +15% |
| #12 | Pydantic AIPydantic AI is a typed Python agent framework where models are swapped with a string, with tools, structured outputs, durable execution… | 21k | 1.7M | +20% |
| #13 | DifyDify is an open-source LLM app development platform for building agentic workflows, RAG pipelines, and agents on a visual canvas. | 160.1k | – | – |
| #14 | Claude Agent SDKClaude Agent SDK is a Python SDK for building agents that interact programmatically with Claude Code, including its tools, custom tools,… | 8.4k | 25.6M | +15% |
| #15 | smolagentssmolagents is a minimal Python library from Hugging Face for building agents that write their actions as Python code to call tools. | 30.2k | 152.7k | +29% |
| #16 | CopilotKitCopilotKit is an open-source framework that connects apps to AI agents with chat, generative UI, shared state, and human approvals. | 38.4k | 653.6k | +8% |
| #17 | SkillOptSkillOpt is a Python text-space optimizer that trains reusable natural-language skill documents for frozen LLM agents without changing… | 18.8k | 6.4k | +19% |
| #18 | MemOSSelf-evolving memory OS for LLM & AI Agents: ultra-persistent memory, hybrid-retrieval, and cross-task skill reuse, with 35.24% token… | 12.2k | 529 | +12% |
| #19 | Google ADKAn open-source, code-first Python toolkit for building, evaluating, and deploying sophisticated AI agents with flexibility and control. | 22.1k | 2.4M | +7% |
| #20 | n8nn8n is a fair-code workflow automation platform for building AI agents and workflows with a visual canvas plus custom code, self-hosted… | 209.2k | 147.7k | +2% |
| #21 | Strands AgentsStrands Agents is an open-source SDK for building and running AI agents in Python and TypeScript, with any model and any cloud. | 9k | 8.9M | +1% |
| #22 | A2A ProtocolA2A Protocol is an open protocol that lets opaque AI agents built on different frameworks discover each other, communicate, and collaborate. | 26.4k | 2.9M | +6% |
| #23 | AgnoAgno is a Python framework and runtime for building agents, running them as a service, and managing the platform through a web UI. | 43k | 514.9k | +4% |
| #24 | DSPyDSPy: The framework for programming—not prompting—language models | 38.9k | 1.3M | +2% |
| #25 | RayRay is an open source AI compute engine with a core distributed runtime and libraries for scaling Python and ML workloads. | 44.2k | 3.7M | +5% |
| #26 | Microsoft Agent FrameworkA framework for building, orchestrating and deploying AI agents and multi-agent workflows with support for Python and .NET. | 14.4k | 47.3k | −3% |
| #27 | AgentKit by InngestAgentKit: Build multi-agent networks in TypeScript with deterministic routing and rich tooling via MCP. | 959 | 37.9k | +12% |
| #28 | HaystackOpen-source AI orchestration framework for building context-engineered, production-ready LLM applications. Design modular pipelines and… | 26.9k | 140.8k | +3% |
| #29 | VoltAgentVoltAgent is an AI agent engineering platform built on an open-source TypeScript framework, with the VoltOps Console for observability… | 10.9k | 49.8k | +7% |
| #30 | OumiOumi is an open-source Python platform for fine-tuning, evaluating, and deploying open text and multimodal models, including agentic… | 9.4k | 9.6k | +28% |
| #31 | CrewAICrewAI is an open-source Python framework for building multi-agent workflows, using role-based agent Crews and event-driven Flows. | 60.4k | 589.4k | −6% |
| #32 | Semantic KernelIntegrate cutting-edge LLM technology quickly and easily into your apps | 28.7k | 83.4k | +12% |
| #33 | LangChainThe agent engineering platform. | 148.8k | 41.1M | −1% |
| #34 | AutoGenA programming framework for agentic AI | 61.7k | – | – |
| #35 | MetaGPT🌟 The Multi-Agent Framework: First AI Software Company, Towards Natural Language Programming | 71.1k | – | – |
| #36 | LangflowLangflow is a powerful tool for building and deploying AI-powered agents and workflows. | 156.2k | 8.3k | −9% |
| #37 | elizaOSOpen source agentic operating system | 19.7k | 7.6k | −16% |
| #38 | Agent LightningThe absolute trainer to light up AI agents. | 18.9k | 3.4k | −19% |
| #39 | LangChain4jLangChain4j is an idiomatic, open-source Java library for building LLM-powered applications on the JVM. It offers a unified API over… | 13.3k | – | – |
| #40 | Spring AIAn Application Framework for AI Engineering | 9.6k | – | – |
| #41 | LlamaIndexLlamaIndex is the document processing platform for AI | 52.8k | 1.5M | −7% |
| #42 | CAMELCAMEL is an open-source Python framework for building multi-agent systems with LLM-driven agents, tools, memory, and synthetic data… | 18k | 15.3k | −6% |
| #43 | FlowiseFlowise is an open source TypeScript platform for building AI agents, chatbots and multi-agent workflows visually. The project is now… | 55.5k | 5.6k | +76% |
| #44 | Agentic Context Engine🧠 Make your agents learn from experience. Now available as a hosted solution at kayba.ai | 2.6k | 2.5k | +99% |
FAQ
What is the fastest-growing of the AI agent frameworks right now?
Harness² ranked #1 among AI agent frameworks on the Devtoolwatch Board in the week of Oct 25–31, 2026, with a momentum score of 95 out of 100.
Which of the AI agent frameworks has the most GitHub stars?
Of the AI agent frameworks ranked in the week of Oct 25–31, 2026, n8n has the most GitHub stars: 209.2k.
Which of the AI agent frameworks is downloaded the most?
Vercel AI SDK's main package had the most downloads of the ranked AI agent frameworks: 42.6M in the week of Oct 25–31, 2026.
How does Devtoolwatch rank AI agent frameworks?
Every Monday the Board averages four percentile ranks: new GitHub stars from daily snapshots, new stars for the repo's size, added npm and PyPI downloads, and download growth beyond the market. Star spikes without forks, downloads or Hacker News to back them are held back.
Rankings come from Devtoolwatch's daily GitHub snapshots and the npm and PyPI download APIs. How the ranking works.