• Fix a race in OAuth token refresh that could write a stale token after a parallel refresh succeeded; the lock now compares accessToken against the value held at lock acquisition time.
• Token-refresh HTTP timeout raised from 15s to 30s — long-tail refreshes no longer fail when the IDP is slow.
• The enter chord is no longer suggested in the task-picker hint row for mcp_task items, where viewing isn't supported.
• Fixed a sort instability in the prompt-completion suggester — scores are now bucketed by tenths before falling back to recent-usage tiebreak, removing a flicker on every keystroke.
• Background spare-claim failures now propagate the inner error to the caller (previously only the outer "Background service unreachable" message survived).
• The history-picker's last-match search now case-folds the query before scanning entries.
• The prompt-caching-scope-2026-01-05 plus other betas dropped only the tengu_slate_reef gating; no functional change.
• Web search results no longer enable prompt caching (caching was forced off for that path), avoiding wasted cache reads on per-call ephemeral tool schemas.

(Search for "tengu_oauth_token_refresh_race_resolved", "tengu_oauth_token_refresh_starting", "\"mcp_task\"", and "enablePromptCaching: !1" to verify each.)