import type { Message, ToolResult } from "./contracts.js";
export declare const DEFAULT_TOOL_RESULT_FOLD_MIN_AGE_TURNS = 2;
export declare const DEFAULT_TOOL_RESULT_FOLD_MIN_BYTES = 4096;
export declare const DEFAULT_TOOL_RESULT_FOLD_MAX_SUMMARY_BYTES = 512;
export declare const HARD_TOOL_RESULT_FOLD_MAX_SUMMARY_BYTES = 4096;
export declare const TOOL_RESULT_FOLD_TURN_METADATA_KEY: "prismToolResultTurn";
export interface ToolResultFoldInput {
    readonly sessionId: string;
    readonly runId: string;
    readonly turn: number;
    readonly toolCallId: string;
    readonly toolName: string;
    readonly text: string;
}
export interface ToolResultFoldOptions {
    readonly minAgeTurns?: number;
    readonly minBytes?: number;
    readonly maxSummaryBytes?: number;
    readonly summarize: (input: ToolResultFoldInput) => Promise<string> | string;
}
export interface ResolvedToolResultFoldOptions {
    readonly minAgeTurns: number;
    readonly minBytes: number;
    readonly maxSummaryBytes: number;
    readonly summarize: (input: ToolResultFoldInput) => Promise<string> | string;
}
export interface FoldToolResultsContext {
    readonly sessionId: string;
    readonly runId: string;
    readonly turn: number;
    readonly signal?: AbortSignal;
}
/** Run overrides agent; disabled when neither supplies `summarize`. */
export declare function resolveToolResultFold(run?: ToolResultFoldOptions, agent?: ToolResultFoldOptions): ResolvedToolResultFoldOptions | undefined;
/** Projection-only fold for history tool messages; does not mutate the input array. */
export declare function foldToolResultHistory(history: readonly Message[], options: ResolvedToolResultFoldOptions, context: FoldToolResultsContext): Promise<readonly Message[]>;
/** Projection-only fold for in-flight tool results before message conversion. */
export declare function foldToolResults(results: readonly ToolResult[], options: ResolvedToolResultFoldOptions, context: FoldToolResultsContext): Promise<readonly ToolResult[]>;
export declare function formatFoldedToolResult(summary: string): string;
export declare function foldedToolResultHeader(toolName: string, toolCallId: string, summary: string): string;
/** Text the fold summarizes for one tool result: the payload JSON, then any text blocks.
 *  Shared with the attention compiler so both hash/summarize the same bytes. */
export declare function toolResultFoldText(result: unknown, error: unknown, extra?: readonly {
    readonly type: string;
}[]): string;
/** UTF-8 cap that never splits a multi-byte character. Shared with the attention
 *  compiler's host-summarize path so both cap host text identically. */
export declare function capToolResultSummary(summary: string, maxBytes: number): string;
/** Provider turn per history index: assistant messages advance the turn, tool rows use
 *  their `prismToolResultTurn` stamp when present and the last assistant turn otherwise.
 *  Shared with the attention compiler so age gates match the fold exactly. */
export declare function inferToolResultTurns(history: readonly Message[]): readonly number[];