/**
 * Read-back is mandatory, not an optimisation. Codex stores what it is given without validating
 * it and drops an item type it does not know without a word (C-6), so the only evidence of what
 * was stored is what can be read back off disk (FR-52).
 */
import type { AgentRuntime, HomePath, SessionId, StoredSessionFacts, SwitchOutcome } from "./contract.js";
export declare function readBackCodex(home: HomePath, sessionId: SessionId): Promise<StoredSessionFacts>;
/** Codex declares "create-only" (C-2). The landing hands the command back instead (FR-45). */
export declare function switchToCodex(home: HomePath, sessionId: SessionId, _runtime: AgentRuntime): Promise<SwitchOutcome>;