/** Token ceiling on a single tool result as the MODEL sees it, absent an explicit `Limits.maxToolResultTokens`. */
export declare const DEFAULT_MAX_TOOL_RESULT_TOKENS = 8000;
export interface TruncatedToolResult {
    __truncated: {
        originalTokens: number;
        shownTokens: number;
        note: string;
    };
    value: string;
}
/**
 * Bounds a tool result to `maxTokens` as the MODEL will see it, truncating the middle so the
 * head (what happened first) and the tail (the error, the total, the last record) both survive.
 * Returns `value` unchanged (same reference) when it is already within budget.
 */
export declare function truncateForTranscript(value: unknown, maxTokens?: number): unknown | TruncatedToolResult;