Best Open Source anthropic Libraries
A curated list of the most popular GitHub repositories tagged with anthropic. Select any project to visualize its architecture and dive into the codebase using Codyn's AI engine.
#1affaan-m/ECC
The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cursor and beyond.
#2NousResearch/hermes-agent
The agent that grows with you
#3langchain-ai/langchain
The agent engineering platform
#4affaan-m/everything-claude-code
The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cursor and beyond.
#5headroomlabs-ai/headroom
Compress tool outputs, logs, files, and RAG chunks before they reach the LLM. 20% fewer tokens for coding agents, 60-95% fewer tokens for JSON, same answers. Library, proxy, MCP server.
#6Aider-AI/aider
aider is AI pair programming in your terminal
#7code-yeongyu/oh-my-openagent
omo; the best agent harness - previously oh-my-opencode
#8BerriAI/litellm
Python SDK, Proxy Server (AI Gateway) to call 100+ LLM APIs in OpenAI (or native) format, with cost tracking, guardrails, loadbalancing and logging. [Bedrock, Azure, OpenAI, VertexAI, Cohere, Anthropic, Sagemaker, HuggingFace, VLLM, NVIDIA NIM]
#9diegosouzapw/OmniRoute
Never stop coding. Free MIT AI gateway: one endpoint, 290+ providers (90+ free), 500+ models — Kimi, Claude, GPT, OpenAI, 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 500+ contributors
#10thedotmack/claude-mem
A Claude Code plugin that automatically captures everything Claude does during your coding sessions, compresses it with AI (using Claude's agent-sdk), and injects relevant context back into future sessions.
#11danny-avila/LibreChat
Enhanced ChatGPT Clone: Features Agents, MCP, DeepSeek, Anthropic, AWS, OpenAI, Responses API, Azure, Groq, o1, GPT-5, Mistral, OpenRouter, Vertex AI, Gemini, Artifacts, AI model switching, message search, Code Interpreter, langchain, DALL-E-3, OpenAPI Actions, Functions, Secure Multi-User Auth, Presets, open-source for self-hosting. Active.
#12asgeirtj/system_prompts_leaks
Collection of extracted System Prompts from popular chatbots like ChatGPT, Claude & Gemini
#13wshobson/agents
Intelligent automation and multi-agent orchestration for Claude Code
#14davila7/claude-code-templates
CLI tool for configuring and monitoring Claude Code
#15hesreallyhim/awesome-claude-code
A curated list of awesome skills, hooks, slash-commands, agent orchestrators, applications, and plugins for Claude Code by Anthropic
#16simstudioai/sim
Build, deploy, and orchestrate AI agents. Sim is the central intelligence layer for your AI workforce.
#17can1357/oh-my-pi
⌥ AI Coding agent for the terminal — hash-anchored edits, optimized tool harness, LSP, Python, browser, subagents, and more
#18dyad-sh/dyad
Local, open-source AI app builder for power users ✨ v0 / Lovable / Replit / Bolt alternative 🌟 Star if you like it!
#19stackblitz/bolt.new
Prompt, run, edit, and deploy full-stack web applications. -- bolt.new -- Help Center: https://support.bolt.new/ -- Community Support: https://discord.com/invite/stackblitz
#20vxcontrol/pentagi
✨ Fully autonomous AI Agents system capable of performing complex penetration testing tasks
#21aden-hive/hive
Outcome driven agent development framework that evolves
#22rtk-ai/rtk
CLI proxy that reduces LLM token consumption by 60-90% on common dev commands. Single Rust binary, zero dependencies
#23xonsh/xonsh
🐚 Python-powered shell. Full-featured, cross-platform and AI-friendly.
#24friuns2/BlackFriday-GPTs-Prompts
List of free GPTs that doesn't require plus subscription
#25travisvn/awesome-claude-skills
A curated list of awesome Claude Skills, resources, and tools for customizing Claude AI workflows — particularly Claude Code
#26Arize-ai/phoenix
AI Observability & Evaluation
#27mnfst/manifest
Connect Your Agents And Harnesses With Any Provider 🦚
#28lidge-jun/opencodex
Universal provider proxy for OpenAI Codex & Claude Code — use any LLM (Claude, Gemini, Grok, DeepSeek, Ollama…) with Codex CLI, App, SDK, and Claude Code
#29MCPJam/inspector
Testing and evaluation platform to chat, inspect, and debug MCP servers, MCP apps, and ChatGPT apps.
#30waybarrios/vllm-mlx
OpenAI and Anthropic compatible server for Apple Silicon. Run LLMs and vision-language models (Llama, Qwen-VL, LLaVA) with continuous batching, MCP tool calling, and multimodal support. Native MLX backend, 400+ tok/s. Works with Claude Code.
#31shiwenwen/hope-agent
🦭 会记忆、能持续推进目标、会动态编排多 Agent 的跨端桌面 AI 助手，也可服务化常驻 NAS / 云端 | A cross-device desktop AI agent with memory, autonomous goals, dynamic workflows, and headless deployment
#32modu-ai/moai-adk
Agentic development harness for Claude Code — SPEC-driven plan/run/sync, TRUST 5 quality gates, model+effort routing, and Claude×GLM multi-LLM cost control. Single Go binary, 16 languages, zero deps.
#33asklokesh/loki-mode
Multi-agent autonomous SDLC framework. Spec to deployed app. PRD, GitHub issue, OpenAPI/JSON/YAML, or one-line brief. 5 AI providers, 8 quality gates.
#34gobii-ai/gobii-platform
Your easy to use, always-on AI workforce 👾
#35davekilleen/Dex
Your AI Chief of Staff — a personal operating system starter kit that adapts to your role. No coding required.
#36nanvon/cc-bar
Native macOS menu bar app: track quota, usage and cost for Codex (multi-account) and Claude Code, from your menu bar or a desktop floating HUD. 原生 macOS 菜单栏 App：支持 Codex 多账号与 Claude Code，在菜单栏或桌面悬浮窗实时查看额度、本地用量与消费。
#37Oaklight/llm-rosetta
Production-ready LLM API translation layer for Python — bidirectional conversion between OpenAI, Anthropic & Google formats via hub-and-spoke IR. Optional API gateway. Streaming & non-streaming. Zero core deps. Contributions welcome!