Function deriveTitle

src/bridge/initReplBridge.ts:555–569

* Quick placeholder title: strip display tags, take the first sentence, * collapse whitespace, truncate to 50 chars. Returns undefined if the result * is empty (e.g. message was only ). Replaced by * generateSessionTitle once Haiku resolves (~1-15s).

(raw: string)

 * generateSessionTitle once Haiku resolves (~1-15s).
 */
function deriveTitle(raw: string): string | undefined {
  // Strip <ide_opened_file>, <session-start-hook>, etc. — these appear in
  // user messages when IDE/hooks inject context. stripDisplayTagsAllowEmpty
  // returns '' (not the original) so pure-tag messages are skipped.
  const clean = stripDisplayTagsAllowEmpty(raw)
  // First sentence is usually the intent; rest is often context/detail.
  // Capture group instead of lookbehind — keeps YARR JIT happy.
  const firstSentence = /^(.*?[.!?])\s/.exec(clean)?.[1] ?? clean
  // Collapse newlines/tabs — titles are single-line in the claude.ai list.
  const flat = firstSentence.replace(/\s+/g, ' ').trim()
  if (!flat) return undefined
  return flat.length > TITLE_MAX_LEN
    ? flat.slice(0, TITLE_MAX_LEN - 1) + '\u2026'
    : flat
}