Token-based systems fail in production when APIs treat tokens as opaque blobs of trust. Validation, storage, propagation, and revocation all need explicit handling rules, especially in multi-service architectures.

Validate Every Request

APIs should verify signature, issuer, audience, expiration, and any required tenant or role claims before executing business logic. Those checks belong at the edge of the service, not scattered through handlers.

Reduce Token Exposure

Keep tokens out of logs, browser storage where possible, and debugging traces. If tokens move between services, use short lifetimes and narrow scopes so compromise windows stay small.

Prepare for Revocation

Secret rotation, refresh-token invalidation, and emergency tenant lockout procedures should be part of the operational design. Security incidents rarely wait for the next sprint.