tengu_event_loop_stall

A Claude Code feature flag, read out of the shipped bundle. It has been in the build since v2.1.267, including the newest one read.

Releases whose published page names tengu_event_loop_stall.

1. v2.1.288 2 Oct 2026
   Typing now clears queued screen-reader announcements, and right-click copy drops the selection first

   A keypress now clears held screen-reader announcements and redraws the screen, and right-click copy first removes the current selection

   gate cited by this entry

2. v2.1.288 2 Oct 2026
   Stall detector checks less often while Claude Code is idle

   The stall detector can now drop to a slower checking rate after a quiet period and speed back up when work resumes

   gate cited by this entry

3. v2.1.267 9 Sep 2026
   Non-blocking stdout can now be enabled by a remote flag, not just an env var

   Non-blocking stdout writes can now be turned on remotely, not just via an environment variable

   gate cited by this entry, found in this entry's text

4. v2.1.227 10 Aug 2026
   Event loop stall detector rewritten as a class

   The event-loop stall detector was rewritten as a class with identical behaviour.

   gate cited by this entry, found in this entry's text

Two arms, because they disagree: this account is the one account this site reads and anonymous is a baseline with no identity attached. A reading says nothing about your account, and off cannot rule out a rollout both readings sit outside of. What these readings can and cannot show.

One row per unbroken stretch of one reading, newest first, from snapshots taken every twenty-five minutes or so. No longer carried is not off: it means the flag server stopped returning the gate at all, which is what a retired experiment looks like. The version column is what was installed when the reading was taken, not what caused it.

The earliest release whose published evidence quoted tengu_event_loop_stall was v2.1.267, 9 Sep 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.

One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.

Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the feature flag does. All feature flags.