Open Source AI Coding Tools - Transparent and Extensible Platforms

Official collection of Agent Skills for Obsidian, created by CEO Steph Ango (kepano). Teaches AI agents how to work with Obsidian Markdown (wikilinks, callouts, frontmatter), Bases databases, JSON Canvas whiteboards, the Obsidian CLI, and Defuddle web extraction. Compatible with Claude Code, Codex, and any skills-compatible agent. 13.9k+ GitHub stars.

NTM (Named Tmux Manager) is a free, open-source tool that transforms tmux into a multi-agent command center. Spawn, tile, and coordinate Claude Code, OpenAI Codex, and Gemini CLI agents across named panes with broadcast prompts, a TUI command palette, conflict tracking, context monitoring, and persistent sessions that survive SSH disconnections.

AGENTS.md is an open format standard for documenting instructions that AI coding agents need to work on software projects. Think of it as a README for agents — a dedicated, predictable place for setup commands, code style, testing instructions, and project conventions. Stewarded by the Agentic AI Foundation under the Linux Foundation, it is used by 60,000+ open-source projects.

cmux is a free, open-source native macOS terminal built on libghostty (Ghostty rendering engine) with vertical tabs, split panes, notification rings, and a built-in scriptable browser — designed for managing multiple parallel AI coding agents like Claude Code, Codex, and Gemini CLI.

Top-tier command line AI tool. Lets you pair program with LLMs (Claude 3.5, GPT-4o) directly in your git repo. Edits multiple files effectively.

The spiritual successor to Atom, built in Rust for extreme performance. Features built-in AI collaboration and supports multiple LLMs (Claude, OpenAI, etc.).

Open-source VS Code extension that gives you a full AI dev team in your editor. Supports any model (Claude, GPT, Gemini, local LLMs), custom modes for specialized tasks, and agentic multi-file editing with permission-based control.

The official command-line vibe coding tool from OpenAI. Edits local files, understands your repo, and runs shell commands with your permission. Like Aider, but built by OpenAI.

Open-source AI "vibe coding" platform built on Cloudflare. Generate full-stack apps from prompts, sandboxed in WebContainers, and deploy instantly to Workers. The self-hosted alternative to Bolt.new.

Open-source platform for prompting, running, editing, and deploying full-stack web apps with multiple model providers.

Open directory and leaderboard for reusable AI agent skills. Discover and install modular capabilities that enhance AI coding agents with procedural knowledge through simple one-command installation.

Open-source AI agent that breaks down tasks into steps and executes them using LLMs and tools.

Alibaba's powerful open-source model (Unsloth optimized). Capable of handling huge monorepos with massive context windows. Run it locally or on private cloud.

Open-source AI agent that runs locally for improved privacy and control.

Open-source toolkit for Spec-Driven Development: scaffold specs, plans, and tasks in your repo, then run agent commands to implement changes with the AI tool you prefer.

Open registry for verified agent skills with 3,500+ skills. Discover and install quality-focused skills for Claude Code, Cursor, Windsurf, and other AI coding agents with community verification.

Cloud platform for deploying web services, static sites, background workers, cron jobs, and managed PostgreSQL — all with flat monthly pricing and a generous free tier. Render supports auto-deploys from Git, built-in SSL, and private networking with zero DevOps configuration.

Official open-source catalog of Agent Skills for OpenAI Codex. Skills are reusable folders of instructions, scripts, and resources that extend Codex with task-specific capabilities like deployment, design implementation, security analysis, and testing.

Web scraping API that converts any webpage into clean Markdown or structured JSON for AI consumption. Features intelligent crawling, AI-powered extraction, and JavaScript rendering for building AI-ready data pipelines.

Open-source CLI tool that generates entire codebases from natural-language prompts. Supports OpenAI, Anthropic, and open-source models with customizable agent identity and vision input for diagrams.

Open-source multi-agent AI framework that runs in a Dockerized sandbox with code execution, browser automation, subordinate agents, and a memory system for building autonomous coding and research workflows.

Open-source Firebase alternative built on Postgres. Supabase combines database, auth, storage, edge functions, realtime sync, and AI-ready vectors into a single backend platform for shipping full-stack products fast.

Open-source LLM observability and engineering platform for tracing, evaluating, and debugging AI applications. Langfuse provides production-grade monitoring with trace spans, cost tracking, prompt management, evaluation datasets, and a playground — all with no per-seat fees and a self-hostable MIT-licensed core.

Community prompt and chain repository integrated with LangSmith. LangChain Hub lets developers discover, share, and version-control prompt templates, agent configurations, and chain definitions — a prompt registry that connects directly to the LangChain ecosystem for rapid AI prototyping.

Official collection of Jupyter notebooks and code recipes from Anthropic for building with the Claude API. Covers tool use, MCP integration, agent patterns, extended thinking, RAG, prompt caching, multimodal capabilities, and production patterns.

Official collection of guides, quickstarts, and Jupyter notebooks from Google for building with the Gemini API. Covers multimodal prompting, function calling, grounding with Google Search, context caching, audio/video understanding, and agent patterns.

Open-source SDK from Microsoft for integrating LLMs into applications using C#, Python, and Java. Semantic Kernel provides an agent framework, plugin architecture, prompt template engine, planner, and memory connectors — designed for enterprise AI orchestration with Azure OpenAI and other providers.

Open-source AI coding agent for VS Code, JetBrains, and CLI that supports 500+ AI models. Features agentic workflows, inline autocomplete, browser automation, and an orchestrator mode that breaks complex tasks into coordinated subtasks.

Open-source CLI tool for Continuous AI that runs async agents on pull requests to enforce team rules, catch issues, and accelerate software shipping.

Free, open-source personal AI assistant that runs locally on your devices. Integrates with WhatsApp, Telegram, Discord, and iMessage to perform real-world tasks: managing emails, calendars, files, and automating workflows.