export declare const DEFAULT_AUTH_MODE: "acp";
export declare const AUTH_MODE_ENV_KEY: "CSS_AUTH_MODE";
export type AuthMode = 'acp' | 'acl' | 'allow-all';
export declare function normalizeAuthMode(value: string | null | undefined, fallback?: AuthMode): AuthMode;
export declare function resolveAuthModeInput(value: AuthMode | string | null | undefined, env?: Record<string, string | undefined>): AuthMode;
export declare function resolveAuthModeFromEnv(env: Record<string, string | undefined>): AuthMode;
export declare function applyAuthModeEnv<T extends Record<string, string | undefined>>(env: T, mode: AuthMode): T & Record<typeof AUTH_MODE_ENV_KEY, AuthMode>;
export declare function isAuthModeEnvKey(key: string): boolean;