# ApiKeyAuth Configuration for classic API-key authentication. ```ts export type ApiKeyAuth = RequireExactlyOne; ``` Helper definitions for the constraints above (kept here to avoid extra page reads): ```ts export type Prettify = { [K in keyof T]: T[K]; } & {}; export type RequireExactlyOne = Prettify & { [K in Keys]-?: { [P in K]-?: NonNullable; } & { [P in Exclude]?: null | undefined; }; }[Keys]>; ``` [TypeScript](../../typescript.md) Related types — open only those used by your request: - [ApiKeyAuthBase](ApiKeyAuthBase.md)