import { LogtoError } from './errors';
export declare class LogtoEnvValidationError extends LogtoError {
    constructor(mode: string, missingVars: string[]);
}
export type EnvRequirement = 'always' | 'client' | 'optional';
export interface EnvVarEntry {
    newName: string;
    legacyName: string;
    requirement: EnvRequirement;
    description: string;
}
export declare const LOGTO_ENV_REGISTRY: EnvVarEntry[];
export declare function resolveEnv(newName: string, legacyName: string): string | undefined;
export declare function resolveEnvOrThrow(newName: string, legacyName: string): string;
export declare function validateLogtoEnv(enableClient: boolean): void;