/**
 * Auto-generated session titles.
 *
 * The default title is the first user message truncated to 60 chars —
 * which makes `/sessions` and `/recall` read like "help me fix the…",
 * "can you add a…". This module replaces that with an LLM one-liner
 * ("OAuth2 migration for auth module") generated once per session, in
 * the background, after the session has enough content to summarize.
 *
 * Design notes:
 *   - Fire-and-forget from saveSession. Never blocks a save.
 *   - One-shot: once `aiTitle` is written to the session file, the
 *     generator early-returns. An in-flight guard prevents concurrent
 *     duplicate calls during the 5s autosave cadence.
 *   - Uses the user's active model via chat() — a 4-8 word completion
 *     is negligible cost, and respecting the active model means it
 *     works for every provider without special-casing.
 */
import type { Message } from '../config/index.js';
/**
 * Generate a short title from a session's history, or null if there
 * isn't enough to summarize (fewer than 3 non-system messages) or the
 * LLM call fails. The caller persists the result.
 */
export declare function generateSessionTitle(history: Message[]): Promise<string | null>;