import type { ProviderErrorLike, EnvVarValidationResult } from "../types/index.js";
/**
 * Get the best available provider based on real-time availability checks
 * Enhanced version consolidated from providerUtils-fixed.ts
 * @param requestedProvider - Optional preferred provider name
 * @returns The best provider name to use
 */
export declare function getBestProvider(requestedProvider?: string): Promise<string>;
/**
 * Validate environment variable values for a provider
 * Addresses GitHub Copilot comment about adding environment variable validation
 * @param provider - Provider name to validate
 * @returns Validation result with detailed information
 */
export declare function validateProviderEnvVars(provider: string): EnvVarValidationResult;
/**
 * Check if a provider has the minimum required environment variables
 * NOTE: This only checks if variables exist, not if they're valid
 * For validation, use validateProviderEnvVars instead
 * @param provider - Provider name to check
 * @returns True if the provider has required environment variables
 */
export declare function hasProviderEnvVars(provider: string): boolean;
/**
 * Get available provider names
 * @returns Array of available provider names
 */
export declare function getAvailableProviders(): string[];
/**
 * Validate provider name
 * @param provider - Provider name to validate
 * @returns True if provider name is valid
 */
export declare function isValidProvider(provider: string): boolean;
/**
 * Type guard for provider error
 */
export declare function isProviderError(error: unknown): error is ProviderErrorLike;