export declare const MAX_LINES = 2000;
export declare const MAX_BYTES: number;
/** @deprecated Use MAX_BYTES instead. Kept for backwards compatibility with tests. */
export declare const MAX_CHARS: number;
export interface TruncateResult {
    content: string;
    truncated: boolean;
    totalLines: number;
    keptLines: number;
}
/**
 * Truncate from the end — keep the first N lines.
 * Used by the read tool.
 */
export declare function truncateHead(content: string, maxLines?: number, maxBytes?: number): TruncateResult;
/**
 * Truncate from the beginning — keep the last N lines.
 * Used by the bash tool.
 */
export declare function truncateTail(content: string, maxLines?: number, maxBytes?: number): TruncateResult;
/** Hard cap on the descriptor appended to a truncation note. */
export declare const OMITTED_NOTE_MAX_CHARS = 300;
/**
 * Describe WHAT a truncation dropped, so the agent can decide whether to fetch
 * the rest (modelled on headroomlabs-ai/headroom PR #3635's CCR descriptor):
 * error/warning line counts, distinct error codes / exception names, distinct
 * source files referenced by diagnostics/stack frames, and the first few
 * distinct error lines. Labels, files and sample lines already visible in
 * `shown` are left out — the note justifies retrieval, it doesn't restate.
 *
 * Returns `""` when nothing notable was cut (the note stays byte-identical),
 * otherwise `"Omitted part: …."`, never longer than OMITTED_NOTE_MAX_CHARS.
 * Deterministic: first-appearance order, no hashing or randomness.
 */
export declare function describeOmitted(omitted: readonly string[], shown: string): string;
/**
 * `describeOmitted` for a non-positional cut (content-aware compression):
 * the omitted lines are the original lines with no counterpart in `shown`.
 * Repeats collapsed to `line  (×N)` / `(×N similar)` count as shown.
 */
export declare function describeCompressed(original: string, shown: string): string;