Login URLs include a per-organization portal code in the path. The login API expects portalCode in the JSON body together with username and password.
Live org data is accessed through /api/org/{slug}/… routes. After org login, the browser (or your server) holds an httpOnly session cookie. Use credentials: "include" in fetch or equivalent in your HTTP client.
API keys you create in the org dashboard are stored as organization-scoped secrets and are intended for server-to-server Bearer authentication (for example a future or partner-enabled /api/v1 surface). Until that surface is enabled for your tenant, prefer the org session + /api/org/… pattern from your backend.