Function summarizeRecentActivities

src/utils/collapseReadSearch.ts:1074–1109

(
  activities: readonly {
    activityDescription?: string
    isSearch?: boolean
    isRead?: boolean
  }[],
)

 * last activity's description for non-collapsible tool uses.
 */
export function summarizeRecentActivities(
  activities: readonly {
    activityDescription?: string
    isSearch?: boolean
    isRead?: boolean
  }[],
): string | undefined {
  if (activities.length === 0) {
    return undefined
  }
  // Count trailing search/read activities from the end of the list
  let searchCount = 0
  let readCount = 0
  for (let i = activities.length - 1; i >= 0; i--) {
    const activity = activities[i]!
    if (activity.isSearch) {
      searchCount++
    } else if (activity.isRead) {
      readCount++
    } else {
      break
    }
  }
  const collapsibleCount = searchCount + readCount
  if (collapsibleCount >= 2) {
    return getSearchReadSummaryText(searchCount, readCount, true)
  }
  // Fall back to most recent activity with a description (some tools like
  // SendMessage don't implement getActivityDescription, so search backward)
  for (let i = activities.length - 1; i >= 0; i--) {
    if (activities[i]?.activityDescription) {
      return activities[i]!.activityDescription
    }
  }
  return undefined
}