Stress-test an idea with opposing arguments, failure scenarios, and a premortem before committing resources.
Install
npx skills add alivirgo/Major-AI-Skills --skill play-devils-advocatenpx skills add alivirgo/Major-AI-Skills --skill play-devils-advocate -a claude-code -gnpx skills add alivirgo/Major-AI-Skills --skill play-devils-advocate -a codex -ggemini skills install https://github.com/alivirgo/Major-AI-Skills.git --path skills/play-devils-advocategh skill install alivirgo/Major-AI-Skills play-devils-advocategit clone --depth 1 https://github.com/alivirgo/Major-AI-Skills /tmp/alivirgo__Major-AI-Skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/alivirgo__Major-AI-Skills/skills/play-devils-advocate ~/.claude/skills/play-devils-advocate # Claude Code
cp -R /tmp/alivirgo__Major-AI-Skills/skills/play-devils-advocate ~/.agents/skills/play-devils-advocate # Codex, Cursor, Gemini CLI, Copilot, OpenCode