Replaces localhost:3000 style URLs with stable names like https://myapp.localhost so you stop hitting EADDRINUSE conflicts, memorizing which port belongs to which service, or watching AI agents test the wrong endpoint. Works as a global install or per-project dev dependency, auto-assigns ports in the 4000-4999 range, and runs an HTTPS proxy on 443 that routes by subdomain. The monorepo support is the real draw: one config maps apps/web and apps/api to clean URLs, and it auto-discovers workspaces from pnpm or package.json. Handles git worktrees by prefixing branch names as subdomains. Most frameworks respect the PORT variable, but it auto-injects flags for Vite and friends that don't.
npx skills add https://github.com/vercel-labs/portless --skill portless