Scale AI is a self-hosted control plane for multi-tenant AI SaaS. It meters provider COGS, enforces hard and soft budgets, routes approved models, recovers durable BullMQ jobs, manages versioned pgvector retrieval, and joins usage to revenue. The operator console makes contribution margin, payback, and COGS visible per tenant. The public demo uses synthetic data; the download includes editable source, Docker Compose, OpenAPI, Node and PHP SDKs, and a local mock provider.