tengu_ccr_keepalive_after_stop_enabled
A Claude Code feature flag, read out of the shipped bundle. It was in the build from v2.1.277 and was gone by v2.1.281.
Remote (CCR) sessions gain keepalive messages after a turn stops, currently off by default
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.277.
In the changelogs
2Releases whose published page names tengu_ccr_keepalive_after_stop_enabled.
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v2.1.281
Keepalive-after-stop flag check refactored to take the flag name
The keepalive-after-stop check was restructured to take its flag name as a parameter, with no change in behaviour
gate cited by this entry, found in this entry's text
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v2.1.277
New keepalive frames after Stop for remote (CCR) sessions, gated off by default
Remote (CCR) sessions gain keepalive messages after a turn stops, currently off by default
gate cited by this entry, found in this entry's text, named in this entry
Gate readings
2| Release | Resolved | This account | Anonymous | Compiled default |
|---|---|---|---|---|
| v2.1.281 read on another version | On for this account, and not off by default | on | on | not a boolean we can read |
| v2.1.277 read on another version | Off in both readings | off | off | off |
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.
Flag server, over time
6| Read as | Reading | From | Until | Version installed |
|---|---|---|---|---|
| anonymous | on | 2026-10-17T05:30:04Z | 2026-11-06T13:45:04Z | v2.1.302 to v2.1.318 |
| this account | on | 2026-09-21T15:25:05Z | 2026-11-06T13:45:04Z | v2.1.278 to v2.1.318 |
| anonymous | no longer carried | 2026-10-17T05:25:57Z | 2026-10-17T05:25:57Z | v2.1.302 |
| anonymous | on | 2026-09-21T14:35:05Z | 2026-10-17T05:10:04Z | v2.1.278 to v2.1.302 |
| this account | off | 2026-09-17T22:30:05Z | 2026-09-21T14:35:05Z | v2.1.274 to v2.1.278 |
| anonymous | off | 2026-09-17T21:45:04Z | 2026-09-21T14:25:05Z | v2.1.274 to v2.1.278 |
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.
First cited
2The earliest release whose published evidence quoted tengu_ccr_keepalive_after_stop_enabled was v2.1.277, 18 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.
Presence across releases
2Build by build
39One 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.