Awesome Harness Engineering

An agentic skills framework & software development methodology that works.

The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cursor and beyond.

The open source coding agent.

Build Agentic workflows, RAG pipelines, with rich AI model and tool support on one collaborative workspace. Deploy on cloud, VPC, or self-hosted, so teams move from prototype to production without rebuilding the stack.

AI agent toolkit: unified LLM API, agent loop, TUI, coding agent CLI

Model Context Protocol Servers

🙌 OpenHands: AI-Driven Development

Production-grade engineering skills for AI coding agents.

Bash is all you need - A nano claude code–like 「agent harness」, built from 0 to 1

The Memory Layer for AI Agents - Drop-in memory infrastructure for AI agents and apps. Context that persists. Built for production.

The best-benchmarked open-source AI memory system. And it's free.

The fastest, litest AI Gateway. Rust core with Python SDK. Call 100+ LLM APIs in OpenAI (or native) format with cost tracking, guardrails, load balancing, and logging [Bedrock, Azure, OpenAI, Anthropic, OpenAI, VertexAI, vLLM, Nvidia NIM]

an open source, extensible AI agent that goes beyond code suggestions - install, execute, edit, and test with any LLM

A collection of notebooks/recipes showcasing some fun and effective ways of using Claude.

Chrome DevTools for coding agents

Never stop coding. Free MIT AI gateway: one endpoint, 330+ providers (90+ free), 1200+ models — Kimi, Claude, GPT, Gemini, GLM, DeepSeek, MiniMax. Works with Claude Code, Codex, Cursor, OpenCode, Cline & Copilot. Quota-aware auto-fallback, RTK+Caveman compression saves 15-95% tokens, MCP/A2A, Desktop/PWA. Built by 320+ contributors

Ultra-lightweight, open-source, self-hosted personal AI agent framework in Python with WebUI, tools, memory, MCP, multi-agent workflows, automation, and chat apps

"CLI-Anything: Making ALL Software Agent-Native" -- CLI-Hub: https://clianything.cc/

Orca is the ADE for working with a fleet of parallel agents. Run any coding agent with your own subscription. Available on desktop, mobile and VPS.

Installable GitHub library of 1,800+ agentic skills for Claude Code, Cursor, Codex CLI, Gemini CLI, Antigravity, and more. Includes specialized plugins, installer CLI, bundles, workflows, and official/community skill collections.

High-performance code intelligence MCP server. Indexes codebases into a persistent knowledge graph — average repo in milliseconds. 158 languages, sub-ms queries, 99% fewer tokens. Single static binary, zero dependencies.

Open-source, community-driven agent harness

Build resilient agents.

Teams-first Multi-agent orchestration for Claude Code

Playwright MCP server

Self-evolving Context Database for AI Agents. Unify Agent Memory, Knowledge RAG and Skills.

Compress tool outputs, logs, files, and RAG chunks before they reach the LLM. 60-95% fewer tokens, same answers. Library, proxy, MCP server.

🪢 Open source AI engineering platform: LLM evals, observability, metrics, prompt management, playground, datasets. Integrates with OpenTelemetry, LangChain, OpenAI SDK, LiteLLM, and more. 🍊YC W23

Cognee is the open-source AI memory platform for agents. Give your AI agents persistent long-term memory across sessions with a self-hosted knowledge graph engine.

Composio powers 1000+ toolkits, tool search, context management, authentication, and a sandboxed workbench to help you build AI agents that turn intent into action.

DeepSeek-native AI coding agent for your terminal. Engineered around prefix-cache stability — leave it running.

A format specification for describing a visual identity to coding agents. DESIGN.md gives agents a persistent, structured understanding of a design system.

The batteries-included agent harness.

Mastra is the modern TypeScript framework for AI-powered applications and agents.

The AI Toolkit for TypeScript. From the creators of Next.js, the AI SDK is a free open-source library for building AI-powered applications and agents

#1 Persistent memory for AI coding agents based on real-world benchmarks

Test your prompts, agents, and RAGs. Red teaming/pentesting/vulnerability scanning for AI. Compare performance of GPT, Claude, Gemini, DeepSeek, and more. Simple declarative configs with command line and CI/CD integration. Used by OpenAI and Anthropic.

Hindsight: Agent Memory That Learns

Debug, evaluate, and monitor your LLM applications, RAG systems, and agentic workflows with comprehensive tracing, automated evaluations, and production-ready dashboards.

Scale computer-use 2.0 with open-source drivers, cross-OS fleets, and benchmarks for training, evaluation, and data generation.

Fast, efficient, battle-tested at Alibaba's scale. Hybrid architecture code review tool: deterministic pipelines + LLM Agent, precise line-level comments, built-in multi-language ruleset (NPE, thread-safety, XSS, SQL injection), OpenAI & Anthropic compatible.

Context window optimization for AI coding agents. Sandboxes tool output (98% reduction), persists session memory, and enforces routing across 17 platforms via MCP + hooks.

The LLM Evaluation Framework

A collection of projects designed to help developers quickly get started with building deployable applications using the Claude API

SkillOpt is a text-space optimizer that trains reusable natural-language skills for frozen LLM agents through trajectory-driven edits, validation-gated updates, and deployable best_skill.md artifacts.

AG-UI: the Agent-User Interaction Protocol. Bring Agents into Frontend Applications.

"OpenHarness: Open Agent Harness with a Built-in Personal Agent--Ohmo!"

Fully autonomous & self-evolving research from idea to paper. Chat an Idea. Get a Paper. 🦞

Open Source framework for voice and multimodal conversational AI

Open-source, secure environment with real-world tools for enterprise-grade agents.