Claudecode/Codex Skills: Open-source collection

OpenAi: A curated list of practical Codex skills for automating workflows across the Codex CLI and API.
https://github.com/openai/skills

Agent: A comprehensive collection of Agent Skills for context engineering, multi-agent architectures, and production agent systems.
https://github.com/muratcankoylan/Agent-Skills-for-Context-Engineering

Awesome Skills: curated collection of AI agent skills organized by categories.
https://github.com/onurkanbakirci/awesome-skills

Obsidian: Agent skills for Obsidian.
https://github.com/kepano/obsidian-skills/tree/main

K-Dense: A set of ready to use scientific skills for Claude.
https://github.com/K-Dense-AI/claude-scientific-skills

Vercel Labs: A collection of skills for AI coding agents.
https://github.com/vercel-labs/agent-skills

Composio: A curated list of practical Codex skills for automating workflows across the Codex CLI and API.
https://github.com/ComposioHQ/awesome-codex-skills