export declare const DEFAULT_MAX_OUTPUT_BYTES = 1048576;
export declare const DEFAULT_MAX_RUNTIME_MS = 1800000;
export declare const HARD_MAX_RUNTIME_MS = 21600000;
export declare const DEFAULT_AWAIT_MS = 30000;
export declare const HARD_AWAIT_MS = 120000;
export declare const DEFAULT_MAX_JOBS_PER_SESSION = 8;
export declare const DEFAULT_JOB_TTL_MS = 21600000;
export declare const DEFAULT_KILL_GRACE_MS = 2000;
export declare const MIN_MAX_RUNTIME_MS = 1000;
export declare const MAX_REGEX_LENGTH = 1024;
export declare const TASK_ID_RE: RegExp;
export type BackgroundShellErrorCode = "CAPABILITY_DISABLED" | "PERMISSION_DENIED" | "INVALID_WORKDIR" | "INVALID_REGEX" | "JOB_NOT_FOUND" | "JOB_LIMIT" | "ID_COLLISION" | "SPAWN_FAILED" | "SUPERVISOR_DISPOSED";
export type BackgroundShellStatus = "running" | "complete" | "error" | "cancelled";
export declare class BackgroundShellError extends Error {
    readonly code: BackgroundShellErrorCode;
    constructor(code: BackgroundShellErrorCode, message: string);
}
export interface BackgroundShellSupervisorOptions {
    /** Directory for `<taskId>.txt` output files. Created on demand. */
    outputDirectory: string;
    /** Shell binary. Defaults to `$SHELL` or `/bin/sh`. */
    shell?: string;
    maxOutputBytes?: number;
    defaultMaxRuntimeMs?: number;
    hardMaxRuntimeMs?: number;
    defaultAwaitMs?: number;
    hardAwaitMs?: number;
    maxJobsPerSession?: number;
    jobTtlMs?: number;
    killGraceMs?: number;
    /** Injectable clock for TTL tests. */
    now?: () => number;
}
export interface BackgroundShellSpawnInput {
    sessionId: string;
    messageId: string;
    command: string;
    workingDirectory: string;
    description?: string;
    maxRuntimeMs?: number;
    signal?: AbortSignal;
}
export interface BackgroundShellAwaitInput {
    sessionId: string;
    taskId: string;
    blockUntilMs?: number;
    regex?: string;
    signal?: AbortSignal;
}
/** Snapshot field order is part of the public contract when JSON-stringified. */
export interface BackgroundShellSnapshot {
    taskId: string;
    status: BackgroundShellStatus;
    runtimeMs: number;
    outputFilePath: string;
    outputLength: number;
    regexRequested: boolean;
    regexMatch: string | null;
    exitCode: number | null;
    signal: string | null;
    truncated: boolean;
}
export interface BackgroundShellSupervisor {
    spawn(input: BackgroundShellSpawnInput): Promise<BackgroundShellSnapshot>;
    await(input: BackgroundShellAwaitInput): Promise<BackgroundShellSnapshot>;
    disposeSession(sessionId: string): Promise<void>;
    disposeAll(): Promise<void>;
    /** Test helper: process-group leader PID while the job is known. */
    getPid(taskId: string): number | null;
}
export declare function createBackgroundShellSupervisor(options: BackgroundShellSupervisorOptions): BackgroundShellSupervisor;