Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.280 Feeds RSS JSON llms.txt Unofficial
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One name

tengu_brass_plover

A Claude Code feature flag, read out of the shipped bundle. It has been in the build since v2.1.251, including the newest one read.

Familyfeature flagFeature flags
Builds22of the 122 on this box
First seen v2.1.251 28 Aug 2026
Last seen v2.1.278 19 Sep 2026
Statusin the buildas of v2.1.278

What it is

Artifacts can show who else is viewing live, but only if you set an environment variable.

Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.251.

Presence across releases

1
BuildsHow manyDatesReading
v2.1.251 – v2.1.27822 builds28 Aug 2026 → 19 Sep 2026 in the build

Build by build

22

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.

BuildDateStateThe record behind it
v2.1.25128 Aug 2026·addedverdict: added · default bool:false
v2.1.25231 Aug 2026·presentverdict: present · default bool:false
v2.1.2571 Sep 2026·presentverdict: present · default bool:false
v2.1.2581 Sep 2026·presentverdict: present · default bool:false
v2.1.2592 Sep 2026·presentverdict: present · default bool:false
v2.1.2603 Sep 2026·presentverdict: present · default bool:false
v2.1.2614 Sep 2026·presentverdict: present · default bool:false
v2.1.2636 Sep 2026·presentverdict: present · default bool:false
v2.1.2658 Sep 2026·presentverdict: present · default bool:false
v2.1.2668 Sep 2026·presentverdict: present · default bool:false
v2.1.2679 Sep 2026·presentverdict: present · default bool:false
v2.1.26810 Sep 2026·presentverdict: present · default bool:false
v2.1.26911 Sep 2026·presentverdict: present · default bool:false
v2.1.27012 Sep 2026·presentverdict: present · default bool:false
v2.1.27114 Sep 2026·presentverdict: present · default bool:false
v2.1.27214 Sep 2026·presentverdict: present · default bool:false
v2.1.27315 Sep 2026·presentverdict: present · default bool:false
v2.1.27416 Sep 2026·presentverdict: present · default bool:false
v2.1.27517 Sep 2026·presentverdict: present · default bool:false
v2.1.27618 Sep 2026·presentverdict: present · default bool:false
v2.1.27718 Sep 2026·presentverdict: present · default bool:false
v2.1.27819 Sep 2026·presentverdict: present · default bool:false

First cited

1

The earliest release whose published evidence quoted tengu_brass_plover was v2.1.251, 28 Aug 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 above.

ReleaseDateThe span that was quoted
v2.1.25128 Aug 2026tengu_brass_plover

Gate readings

1
ReleaseResolvedThis accountAnonymousCompiled default
v2.1.251 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

20
Read asReadingFromUntilVersion installed
this account on 2026-09-10T21:47:12Z 2026-09-22T15:25:05Z v2.1.268 to v2.1.278
anonymous on 2026-09-03T19:50:04Z 2026-09-22T15:25:05Z v2.1.259 to v2.1.278
this account no longer carried 2026-09-10T21:46:45Z 2026-09-10T21:46:45Z v2.1.268
this account on 2026-09-08T20:36:15Z 2026-09-10T17:40:05Z v2.1.263 to v2.1.267
this account no longer carried 2026-09-08T20:34:58Z 2026-09-08T20:34:58Z v2.1.265
this account on 2026-09-06T02:40:05Z 2026-09-08T18:45:05Z v2.1.261 to v2.1.263
this account no longer carried 2026-09-06T02:36:19Z 2026-09-06T02:36:19Z v2.1.263
this account on 2026-09-03T23:25:05Z 2026-09-06T01:55:04Z v2.1.259 to v2.1.261
this account off 2026-09-03T23:05:05Z 2026-09-03T23:05:05Z v2.1.259
this account on 2026-09-03T23:00:47Z 2026-09-03T23:00:47Z v2.1.260
this account off 2026-09-03T19:25:04Z 2026-09-03T19:50:04Z v2.1.259
anonymous off 2026-09-03T15:55:04Z 2026-09-03T19:25:04Z v2.1.259
this account on 2026-09-02T10:05:06Z 2026-09-03T19:05:05Z v2.1.257 to v2.1.259
anonymous on 2026-09-02T03:20:05Z 2026-09-03T15:25:04Z v2.1.257 to v2.1.259
this account off 2026-09-02T09:25:04Z 2026-09-02T09:25:04Z v2.1.257
this account on 2026-09-02T06:00:05Z 2026-09-02T07:45:04Z v2.1.257
this account off 2026-09-02T03:25:04Z 2026-09-02T03:35:04Z v2.1.257
this account on 2026-09-02T03:20:05Z 2026-09-02T03:20:05Z v2.1.257
this account off 2026-08-28T02:55:04Z 2026-09-02T03:00:06Z v2.1.246 to v2.1.257
anonymous off 2026-08-28T00:55:05Z 2026-09-02T03:00:06Z v2.1.246 to v2.1.257

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.

Names beside it

Every feature flag in the inventory starting tengu_brass, up to twelve of them.

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.