/**
 * `SessionExpiredError` — a remote session that is gone, said ONE way.
 *
 * A managed backend reaps its sessions on its own schedule (a timeout, a stop,
 * a restart), and each service words that differently: AgentCore's Code
 * Interpreter answers with a `ValidationException` saying the session is "not
 * active", a stream error naming an inactive session, or a
 * `ResourceNotFoundException` on a call that addresses nothing but the session.
 * A caller that has to recognise all of those by message text will miss the
 * next one. An adapter recognises them once and raises this instead, so "start
 * a new session" is one `instanceof` away.
 *
 * Raised only on evidence that names the session. A "not found" that could be
 * about something else in the session (a file a read asked for) is not taken
 * as proof the session is gone.
 *
 * It names the session and the signal that said so — never the request that
 * hit it. Nothing reconnects: the session's files and state are gone, and a
 * session name is not an address (names are not unique), so the only honest
 * next step is a new session.
 */
export declare class SessionExpiredError extends Error {
    readonly code: "ERR_SESSION_EXPIRED";
    /** The adapter that raised it, e.g. `'agentCoreCodeRunner'`. */
    readonly backend: string;
    /** The backend's id for the session that is gone. */
    readonly sessionId: string;
    /** The service's own name for the signal that said so, e.g. `'ResourceNotFoundException'`. */
    readonly evidence: string;
    constructor(backend: string, sessionId: string, evidence: string);
}