/**
 * Error hierarchy for @a5c-ai/agent-mux.
 *
 * All errors extend the base AgentMuxError.
 */
import type { AgentName, ErrorCode, ValidationFieldError } from './types.js';
/**
 * Base error class for all agent-mux errors.
 * Provides a machine-readable `code` and a `recoverable` flag.
 */
export declare class AgentMuxError extends Error {
    /** Machine-readable error code. */
    readonly code: ErrorCode;
    /** Whether the operation can be retried. */
    readonly recoverable: boolean;
    constructor(code: ErrorCode, message: string, recoverable?: boolean);
}
/**
 * Thrown when a RunOptions field or API call requires a capability that
 * the target agent or model does not support.
 */
export declare class CapabilityError extends AgentMuxError {
    /** The agent that lacks the capability. */
    readonly agent: AgentName;
    /** The capability that was requested. */
    readonly capability: string;
    /** The model that was targeted, if applicable. */
    readonly model?: string;
    constructor(agent: AgentName, capability: string, model?: string);
}
/**
 * Thrown when input values fail schema or range validation.
 */
export declare class ValidationError extends AgentMuxError {
    /** The field(s) that failed validation. */
    readonly fields: ValidationFieldError[];
    constructor(fields: ValidationFieldError[]);
}
/**
 * Thrown when an agent's authentication state prevents the requested operation.
 */
export declare class AuthError extends AgentMuxError {
    /** The agent with the auth problem. */
    readonly agent: AgentName;
    /** Current auth status. */
    readonly status: 'unauthenticated' | 'expired' | 'unknown';
    /** Human-readable guidance on how to authenticate. */
    readonly guidance: string;
    constructor(agent: AgentName, status: AuthError['status'], guidance: string);
}