TanStack AI adds headless BYOK

This shifts AI infrastructure costs and credential ownership toward users, giving developers a cleaner path to ship multi-provider apps without absorbing every token bill.

• –Client-side key storage can use passkey-encrypted IndexedDB, with memory-only fallback when unavailable
• –Keys still pass through the relay for a single call, so operators must prevent logging and tracing leaks
• –Standardized `/byok` exports reduce adapter-specific integration work across providers
• –BYOK improves margins but adds onboarding friction, rate-limit complexity, and support responsibility for users’ provider accounts