175 listed
Harnesses & SDKs
Frameworks and SDKs for building agents: the Claude Agent SDK, OpenAI Agents SDK, LangGraph, CrewAI and many more. Each page lists languages, packages, MCP and A2A support and how it orchestrates agents, with a link to the page every fact came from.
Showing 1–24 of 101
- 0.867score
Pi Agent Core
Earendil
Minimal TypeScript agent harness with an agent runtime, multi-provider LLM API, terminal UI and coding agent CLI that users extend themselves.
HarnessAFreshness: A★ 117.6K↓ 5.1M/wk - 0.841score
GitHub Copilot SDK
GitHub
Multi-language SDKs for embedding the GitHub Copilot agent runtime, with planning, tool calls and file edits, in your apps.
HarnessAFreshness: A★ 10.6K↓ 1.2M/wk - 0.799score
Genkit
Google
Open-source Firebase framework for AI features and agent workflows in JavaScript, Go, Python and Dart, with model plugins.
HarnessAFreshness: A★ 6.5K↓ 95.8K/wk - 0.791score
ADK for Go
Google
Code-first Go toolkit for building agents with a tool ecosystem, composable multi-agent systems and Cloud Run deployment.
HarnessAFreshness: A★ 8.9K - 0.778score
AgentScope Java
Alibaba Tongyi Lab
Java framework for distributed, long-running agents with typed event streams, permission gating, middleware and subagents.
HarnessAFreshness: A★ 6.1K - 0.777score
ADK for TypeScript
Google
TypeScript toolkit for agents with Zod-typed tools, graph and multi-agent workflows, and Node.js or browser runtimes.
HarnessAFreshness: A★ 1.4K↓ 143.5K/wk - 0.771score
Ax
Ax
DSPy-style toolkit for typed LLM signatures, agents and flows, TypeScript-first with Python, Java, C++, Go and Rust libraries.
HarnessAFreshness: A★ 3K↓ 27.2K/wk - 0.757score
atmosphere
Atmosphere
Java runtime for AI agents that streams tokens and tool events over WebSocket, SSE or gRPC, with human approvals.
HarnessAFreshness: A★ 3.8K - 0.756score
ai
TanStack
TypeScript SDK for streaming chat, tool-calling agents and structured output across model providers and UI frameworks.
HarnessAFreshness: A★ 3.2K - 0.753score
LangChain
LangChain
Python framework of interoperable components and integrations for building agents and LLM apps, with LangGraph and Deep Agents layered above it.
HarnessAFreshness: A★ 148.4K↓ 37.3M/wk - 0.752score
PraisonAI
Mervin Praison
Python framework for multi-agent teams and workflows, with a CLI and Docker, MCP and A2A deployment options.
HarnessAFreshness: A★ 9.3K↓ 4.6K/wk - 0.748score
LangGraph
LangChain
Low-level Python orchestration framework for long-running stateful agents, with durable execution, human review points and short- and long-term memory.
HarnessAFreshness: A★ 43.8K↓ 13.1M/wk - 0.745score
BeeAI Framework
IBM / Linux Foundation
Python and TypeScript framework for multi-agent systems, with MCP and A2A interop, YAML orchestration and OpenTelemetry tracing.
HarnessAFreshness: A★ 3.4K↓ 5.4K/wk - 0.740score
Deep Agents
LangChain
Opinionated agent harness on LangGraph with sub-agents, filesystem access, context management, persistent memory and approval of tool calls.
HarnessAFreshness: A★ 30.6K↓ 1.9M/wk - 0.738score
DSPy
Stanford NLP
Python framework for writing language-model programs as code and optimizing their prompts and weights instead of hand-tuning prompts.
HarnessAFreshness: A★ 38.8K↓ 1.3M/wk - 0.737score
Mastra
Mastra
TypeScript framework for AI agents and apps with graph-based workflows, memory, suspend-and-resume approvals, MCP servers and model routing.
HarnessAFreshness: A★ 29.1K↓ 1.4M/wk - 0.734score
Pydantic AI
Pydantic
Typed Python SDK for building agents with swappable model providers, plus optional capabilities for memory, sub-agents, planning and durable execution.
HarnessAFreshness: A★ 20.8K↓ 1.5M/wk - 0.734score
Google Agent Development Kit (ADK)
Google
Open-source toolkit for building, evaluating and deploying agents in Python, TypeScript, Go, Java and Kotlin, tuned for Gemini but model-agnostic.
HarnessAFreshness: A★ 22K↓ 2.4M/wk - 0.732score
CrewAI
CrewAI
Open-source Python framework for multi-agent workflows, with role-based Crews and event-driven Flows.
HarnessAFreshness: A★ 60.1K↓ 644.6K/wk - 0.731score
stagehand
browserbase
SDK for browser agents with act, observe and extract calls, used from TypeScript and Python to automate sites and pull out structured data.
HarnessAFreshness: A★ 25.8K↓ 996K/wk - 0.729score
Agent Squad
2FastLabs
Open-source framework that routes each user query to one of several AI agents, with Python, TypeScript and Swift runtimes.
HarnessAFreshness: A★ 7.8K↓ 1.5K/wk - 0.727score
Agno
Agno
Python framework and runtime for building agents, serving them over a REST API and MCP server, and managing them from a web control plane.
HarnessAFreshness: A★ 42.9K↓ 519.4K/wk - 0.727score
Vercel AI SDK
Vercel
TypeScript toolkit for AI apps and agents with a unified provider API, streaming, UI hooks and a wrapper for running established agent harnesses.
HarnessAFreshness: A★ 27.5K - 0.722score
LiveKit Agents
LiveKit
Framework for Python or Node.js programs that join LiveKit rooms as realtime voice and video agents.
HarnessAFreshness: A★ 14.9K↓ 963.9K/wk