/**
 * Context Handoff Store — A-CTX-2 persistence layer.
 *
 * Produces, writes, and reads ContextHandoffReceipt files so that
 * downstream processes can verify them without rerunning the upstream agent.
 *
 * Storage layout (under runsRoot/<runId>/):
 *   context-handoff.json        — the receipt produced by this run for the next hop
 *
 * The producerReceiptHash is computed as SHA-256 of the receipt-integrity.json
 * file written by writeLoopRecord. If that file is absent, upstreamIntegrity is
 * set to "evidence_boundary" — the receipt is still written but will not pass
 * verifyContextHandoff.
 */
import type { ContextHandoffArtifact, ContextHandoffClaim, ContextHandoffReceipt } from "../../contracts/index.js";
/** Compute the SHA-256 hex digest of a file's raw bytes. */
export declare function computeFileHash(filePath: string): Promise<string>;
export declare function contextHandoffPath(runsRoot: string, runId: string): string;
/**
 * Persist a ContextHandoffReceipt for this run so the next hop can load it.
 * Overwrites any existing file — callers must not call this more than once per run.
 */
export declare function writeContextHandoff(runsRoot: string, runId: string, receipt: ContextHandoffReceipt): Promise<void>;
/**
 * Load a ContextHandoffReceipt from a previous run.
 * Returns null when the file does not exist (not an error — the consumer
 * must treat absence as a hard gate failure).
 */
export declare function readContextHandoff(runsRoot: string, runId: string): Promise<ContextHandoffReceipt | null>;
export interface BuildHandoffReceiptInput {
    runsRoot: string;
    /** Run that is producing this handoff (the upstream/producer run). */
    producerRunId: string;
    /** Stable identifier for the chain. Shared across all hops. */
    chainId: string;
    /** Optional mission identifier shared across hops. */
    missionId?: string;
    /** Unique ID for this specific handoff crossing. Generated if absent. */
    handoffId?: string;
    /** Verified claims the producer is asserting. All must be state "verified". */
    claims?: ContextHandoffClaim[];
    /**
     * File paths whose SHA-256 hashes should be captured as artifacts.
     * Each file is hashed at call time — callers must call after writing artifacts.
     */
    artifactFiles?: Array<{
        filePath: string;
        label?: string;
        required: boolean;
    }>;
    /** Optional pre-computed artifacts (bypasses file hashing). */
    artifacts?: ContextHandoffArtifact[];
    /** Assumptions that are not yet resolved at handoff time. */
    unresolvedAssumptions?: string[];
    /** Parent handoff IDs for multi-hop lineage. */
    parentHandoffIds?: string[];
    /** Clock override (defaults to new Date().toISOString()). */
    now?: () => string;
}
/**
 * Build a ContextHandoffReceipt from a completed run.
 *
 * - producerReceiptHash is SHA-256 of the receipt-integrity.json file
 *   written by writeLoopRecord. If that file is absent, upstreamIntegrity
 *   is "evidence_boundary".
 * - Artifact hashes are computed from real files at call time.
 */
export declare function buildContextHandoffReceipt(input: BuildHandoffReceiptInput): Promise<ContextHandoffReceipt>;