/**
 * Human-in-the-loop approval — `ctx.approval(name, opts)` uses the durable
 * signal-wait protocol understood by the MemoFlow server.
 *
 * Signal-name convention: an approval named `name` waits on the signal
 * `approval:{name}` (e.g. `ctx.approval('deploy-plan')` waits on signal
 * `approval:deploy-plan`). The server recognizes this prefix and creates an
 * approval work item atomically with the wait. Resolving that work item emits
 * the compatible signal that resumes the workflow. The work item and its
 * audit record, not the checkpoint payload, are the authoritative evidence.
 */
/** Typed payload resolved by `ctx.approval()`. Rejection is not an error —
 * `{ approved: false }` resolves normally; the workflow decides what to do
 * next. Only a malformed payload or a timeout is exceptional. */
export interface ApprovalDecision {
    approved: boolean;
    by?: string;
    comment?: string;
}
/** Prefix applied to an approval `name` to form the underlying signal name. */
export declare const APPROVAL_SIGNAL_PREFIX = "approval:";
/** The signal name a given approval `name` waits on (e.g. `deploy-plan` -> `approval:deploy-plan`). */
export declare function approvalSignalName(name: string): string;
/** True when `signalName` follows the `approval:{name}` convention. */
export declare function isApprovalSignal(signalName: string): boolean;
/** The approval `name` encoded in an `approval:{name}` signal name, or null if it isn't one. */
export declare function approvalNameFromSignal(signalName: string): string | null;
/**
 * Thrown when a resolved approval signal's payload does not match the
 * `ApprovalDecision` shape. Design Law 4 spirit: a malformed payload must
 * fail loudly, never be silently coerced into `{ approved: false }` or
 * similar — that would fabricate an audit record that never happened.
 */
export declare class InvalidApprovalPayloadError extends Error {
    readonly approvalName: string;
    readonly payload: unknown;
    constructor(approvalName: string, payload: unknown);
}
/**
 * Validate and normalize a raw signal payload into an `ApprovalDecision`.
 * Throws `InvalidApprovalPayloadError` rather than coercing malformed input.
 */
export declare function parseApprovalDecision(approvalName: string, payload: unknown): ApprovalDecision;