Identifies costs and benefits not borne by the decision-maker — and how to internalise them. Triggers: 'externality', 'who else is affected', 'costs falling on others', 'side effects', 'spillover', 'the market isn't accounting for this', 'negative externality', 'positive externality', 'social cost vs.
Install
npx skills add human-avatar/skills-for-humanity --skill s4h-economics-externalitiesnpx skills add human-avatar/skills-for-humanity --skill s4h-economics-externalities -a claude-code -gnpx skills add human-avatar/skills-for-humanity --skill s4h-economics-externalities -a codex -ggemini skills install https://github.com/human-avatar/skills-for-humanity.git --path skills/s4h-economics-externalitiesgh skill install human-avatar/skills-for-humanity s4h-economics-externalitiesgit clone --depth 1 https://github.com/human-avatar/skills-for-humanity /tmp/human-avatar__skills-for-humanity
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/human-avatar__skills-for-humanity/skills/s4h-economics-externalities ~/.claude/skills/s4h-economics-externalities # Claude Code
cp -R /tmp/human-avatar__skills-for-humanity/skills/s4h-economics-externalities ~/.agents/skills/s4h-economics-externalities # Codex, Cursor, Gemini CLI, Copilot, OpenCode