How would you design a multi-tenant AI platform where each business gets its own chatbot?

Isolation is the core problem. Each tenant needs their own knowledge base, configuration (prompt, branding, allowed tools), and — critically — data isolation so one business can never retrieve another's documents. Partition vector storage by tenant (separate namespaces/collections or a mandatory tenant filter on every query) and enforce it server-side, never trusting the client. Share the serving infrastructure for efficiency but meter usage and apply per-tenant rate limits and budgets so a noisy tenant can't degrade others. Provide per-tenant evaluation and analytics. Watch for cross-tenant leakage via caching (never share a semantic cache across tenants) and prompt injection. The pattern is shared compute, strictly isolated data and config.