API documentation is useful until it stops matching reality.

A team might maintain accurate OpenAPI specifications, review routes during development, and follow a release process. Yet a few months later, the production environment may contain endpoints that nobody remembers documenting.

Perhaps an older API version is still receiving requests. Maybe a temporary endpoint became part of a permanent workflow. Or a new microservice introduced routes that never made it into the central inventory.

These situations are easy to overlook because the application can continue working normally. The problem becomes apparent when a security team tries to answer a basic question: Do we actually know every API endpoint exposed by our applications?

The gap between documented APIs and running APIs

Traditional API inventories are often built from source code, OpenAPI specifications, gateway configurations, and developer-maintained records.…