/** Log levels understood by MCP clients and mapped to OTel severities. */
export declare enum LogLevel {
    DEBUG = "debug",
    INFO = "info",
    NOTICE = "notice",
    WARNING = "warning",
    ERROR = "error",
    CRITICAL = "critical",
    ALERT = "alert",
    EMERGENCY = "emergency"
}
export type LogFields = Record<string, unknown>;
interface LoggingServer {
    sendLoggingMessage(params: {
        level: LogLevel;
        data: string;
    }): Promise<void>;
}
/**
 * Emits each application log to stderr, to the active OpenTelemetry Logs
 * provider, and optionally to the attached stdio MCP client. stderr is
 * intentional: stdout remains exclusively available for MCP messages.
 */
export declare class Logger {
    private server;
    /** Attach the single stdio MCP connection that should receive log notifications. */
    setServer(server: LoggingServer | null): void;
    debug(message: string, fields?: LogFields, error?: unknown): void;
    info(message: string, fields?: LogFields, error?: unknown): void;
    warning(message: string, fields?: LogFields, error?: unknown): void;
    error(message: string, fields?: LogFields, error?: unknown): void;
    log(level: LogLevel, message: string, fields?: LogFields, error?: unknown): void;
}
export declare const logger: Logger;
export {};