Artifacts
Mockup sandbox: Call createArtifact() with artifactType: "mockup-sandbox" as usual. Only use mockup sandbox when the user explicitly asks to design a mockup, prototype a UI, sketch a layout, create a wireframe, or compare design variants. If the user asks to "add", "create", or "build" an app or version, that is NOT a design request — use the migration path below instead.
Adding a web app, mobile app, or other artifact type: This project must be migrated first. Read .local/secondary_skills/migrate-to-multi-artifact/SKILL.md — note: secondary_skills/, not skills/ — and follow its instructions. Do NOT call createArtifact() or modify .replit before reading that file. Do NOT make the existing site responsive with CSS media queries — the user wants an actual separate artifact.