Every builder ends up with reusable AI skills — SKILL.md files that teach an assistant a specific workflow (generate a branded PDF, scaffold a Chrome extension, write in your voice). Skill Exchange is the marketplace to buy and sell them. The rule: you can't list a skill without proving it works — a real project + screenshot, reviewed by hand. 180+ free; paid skills are one-time and sellers keep 95%. Works with Claude, ChatGPT, Gemini, Cursor & Copilot. Pay in $ or ₹. Browse free, no account.