/**
 * v1.3.2 §9.4 — domain-agnostic guardrail core.
 *
 * Three brakes recur across every autonomous loop SoloSquad runs — a workflow
 * `mode:agentic` stage, the goal pipeline, and agent delegation depth:
 *
 *   1. iteration cap   — stop after N turns
 *   2. budget cap      — stop at a cost ceiling (with an early warning band)
 *   3. loop detection  — stop when the last few outputs are identical (the
 *                        agent is spinning, producing the same thing each turn)
 *
 * `src/engine/guards.ts` already enforces these for the *goal* runtime, but
 * coupled to `GoalSpec`/`PersistentGuide`. This module is the pure, type-free
 * kernel those three call-sites can share: the workflow validator uses
 * {@link GUARDRAIL_KEYS}/{@link hasAnyGuardrail} to check a stage *declares* a
 * brake; a runtime can use the detectors below to *enforce* one.
 */
/** The guardrail fields a `mode:agentic` stage may declare (§6). */
export declare const GUARDRAIL_KEYS: readonly ["max_iterations", "budget_usd", "loop_detection"];
export type GuardrailKey = (typeof GUARDRAIL_KEYS)[number];
/** Does this (loosely-typed, e.g. from YAML) spec declare at least one guardrail? */
export declare function hasAnyGuardrail(spec: unknown): boolean;
/** True once `iteration` (0-based) has reached/exceeded the cap. */
export declare function iterationCapReached(iteration: number, max: number): boolean;
export interface BudgetStatus {
    /** Spend has met/exceeded the ceiling — stop now. */
    exceeded: boolean;
    /** Spend has crossed the warning band (default 90%) but not the ceiling. */
    warning: boolean;
}
/** Evaluate spend against a ceiling. `warnPct` is the fraction (0..1) at which
 *  to raise the early warning. A non-positive `total` disables the cap. */
export declare function budgetStatus(spent: number, total: number, warnPct?: number): BudgetStatus;
/**
 * Flags when the last `window` recorded outputs are all identical — the
 * canonical "the agent is stuck repeating itself" signal. Outputs are compared
 * after trimming + whitespace collapse so trivially-different reformatting of
 * the same content still trips it. Stateful and cheap (keeps only the window).
 */
export declare class LoopDetector {
    private readonly window;
    private readonly recent;
    constructor(window?: number);
    /** Record an output; returns true iff the last `window` outputs are identical. */
    record(output: string): boolean;
    reset(): void;
}