The API key defines ownership

The API account owns billing, API keys and every portfolio created through those keys. ChainsFlow API does not model the integrating product's end users; it exposes paid portfolio resources like CoinStats.

No API-side user provisioning

Keep users and subscriptions in your BFF. Create a portfolio through the standard API, store its returned portfolioId in the BFF, and never send an end-user identity to ChainsFlow API.

Every portfolio lookup is owner-scoped

The API resolves the account from X-API-Key and checks every opaque portfolioId against that owner. A valid UUID alone never grants access. Your BFF separately maps its signed-in users to the portfolio IDs it created.

Model deletion and retention explicitly

Deleting a portfolio removes its encrypted credentials and tracked provider data but cannot revoke the original key at the exchange. The BFF decides which portfolios to delete when one of its own users closes an account.

Enforce product limits before paid mutations

Your BFF owns end-user subscriptions and quotas. Count the user's current accounts there and reject an over-limit connect attempt before sending the weighted creation request; ChainsFlow API only performs the paid portfolio operation.