claude.ai skills sync interval becomes server-configurable, with a new shared-round mode

What

Claude Code periodically checks claude.ai for your skills and syncs them. Two new flags now control that check. A flag here is a setting Anthropic's servers can change without a new version of Claude Code being released.

• tengu_claudeai_skills_sync_interval_minutes sets how often the resync runs. With no server value it falls back to 10 minutes. Any server value is held between 5 and 1440 minutes (once a day).
• The wait between retries after a failed sync (the backoff) is now capped at 4× that interval. It used to be a fixed 10-minute base with a 40-minute cap.
• tengu_claudeai_skills_sync_shared_round falls back to false. When it is on, a session can reuse a recent skills listing that another Claude Code session fetched for the same bucket instead of asking claude.ai again. The session reloads when the shared generation token (a marker that changes when the shared listing changes) moves. It then schedules its next resync for the interval plus a random 30 to 90 seconds.
• The existing skills_sync_round_reused log line is now written from this new sharing path. Before, it came from a simpler check that reused a recent listing.

For tengu_claudeai_skills_sync_shared_round, the flag server returned off for this site's account and for an anonymous baseline, but no reading has been taken under this release. Nothing has been read yet about tengu_claudeai_skills_sync_interval_minutes.

Why

With the fallback values, skills sync behaves as it did before: every 10 minutes, with retries capped at 40 minutes. The server can now change how often every client checks claude.ai for skills, as rarely as once a day. It can also turn on sharing of sync rounds between sessions, which would mean fewer repeated listings when several sessions are open. Either change can happen without a Claude Code update.