interface ProviderEnvAuthResult {
    ok: boolean;
    satisfiedOneOf: boolean;
    malformed: string[];
    message: string;
}
declare function validateEnvPassthrough(value: unknown): string | null;
declare function isUsableEnvValue(value: unknown): value is string;
declare function isUsableHttpUrl(value: unknown): boolean;
declare function validateProviderEnvAuth(providerId: string, forwardedEnv: Readonly<Record<string, string | undefined>> | null | undefined): ProviderEnvAuthResult;
declare const _default: {
    isUsableEnvValue: typeof isUsableEnvValue;
    isUsableHttpUrl: typeof isUsableHttpUrl;
    validateEnvPassthrough: typeof validateEnvPassthrough;
    validateProviderEnvAuth: typeof validateProviderEnvAuth;
};
export = _default;