/**
 * [WHO]: ContextWindowController commits model-authored handoffs at safe request boundaries
 * [FROM]: Depends on session compaction preparation, session entry contracts, and agent message types
 * [TO]: Consumed by AgentSession and context-window regression tests
 * [HERE]: core/runtime/context-window-controller.ts - persisted working-window transitions
 */
import type { AgentMessage } from "@catui/agent-core";
import type { SessionContext, SessionEntry } from "../session/session-manager.js";
interface ContextWindowCapabilities {
    getSessionId(): string;
    getBranch(): SessionEntry[];
    getContextWindow(): number;
    getPromptTokens(): number;
    appendCheckpoint(summary: string, firstKeptEntryId: string, tokensBefore: number, details: unknown): void;
    rebuildContext(): SessionContext;
}
export declare class ContextWindowController {
    private readonly ctx;
    private pending?;
    constructor(ctx: ContextWindowCapabilities);
    /** Queue only; tool execution must finish before the checkpoint is committed. */
    request(handoff: string): boolean;
    cancel(): void;
    /** A no-op until all loop messages have reached the session journal. */
    prepare(messages: AgentMessage[]): AgentMessage[];
}
export {};