APId

APId is a term used to describe an API Identifier, a unique reference assigned to an API or its components within an API portfolio. It is not a formal, universally recognized standard, but it is used in some organizations to improve cataloging and governance of APIs.

Purpose and use: APId helps systems locate, reference, and manage APIs across registries, catalogs, and deployment environments. It supports discovery, dependency mapping, contract testing, access policies, and analytics by providing a stable reference that remains valid even if endpoints or base URLs change. By linking metadata such as title, version, protocol, and licensing, an APId can facilitate cross-provider integration and lifecycle management.

Structure and representation: An APId can be opaque or hierarchical. Common patterns include a namespace-like prefix followed by provider, service, and version components, for example apid:vendor:payments:v2 or urn:apid:vendor:payments:2.0.0. Implementations vary, and some teams store APId as metadata in registries while exposing conventional URLs for runtime access.

Relationships to other concepts: APId is not a replacement for URLs, keys, or tokens. Rather, it complements them by providing a persistent identifier for cataloging and governance. It can be used alongside metadata such as description, owners, compatibility, and licensing, to enable better discovery and management.

Adoption and standards: There is no single formal standard governing APId. Organizations may adopt internal conventions or align APId-like identifiers with existing standards such as URN, UUID, or semantic versioning. Governance practices typically address naming, versioning, and lifecycle management to avoid collisions and ensure backward compatibility.

See also: API, API management, URN, UUID, semantic versioning, API catalog.