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

tengu_version_config

A Claude Code feature flag, read out of the shipped bundle. No mined inventory carries it: everything below comes from what this site has written about it.

Familyfeature flagFeature flags
Builds0of the 122 on this box
First seennever in a mined build
Last seennever in a mined build
Statusnever minedas of v2.1.278

What it is

Startup version-check logic was refactored into its own function, no behavior change

Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.277.

Presence across releases

0

The miner has never read a build containing this name. It is here because a changelog entry of ours names it, which is evidence that it existed and not evidence of which releases carried it. The inventory starts at v2.1.138 and everything older than that was never mined.

First cited

1

The earliest release whose published evidence quoted tengu_version_config 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 above.

ReleaseDateThe span that was quoted
v2.1.27718 Sep 2026tengu_version_config

Gate readings

1
ReleaseResolvedThis accountAnonymousCompiled default
v2.1.277 read on another version Not enough to say no value returned no value returned not a boolean we can read

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

10
Read asReadingFromUntilVersion installed
this account {"minVersion":"1.0.24"} 2026-09-10T21:47:12Z 2026-09-22T05:45:05Z v2.1.268 to v2.1.278
anonymous {"minVersion":"1.0.24"} 2026-08-19T04:25:04Z 2026-09-22T05:45:05Z v2.1.233 to v2.1.278
this account no longer carried 2026-09-10T21:46:45Z 2026-09-10T21:46:45Z v2.1.268
this account {"minVersion":"1.0.24"} 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 {"minVersion":"1.0.24"} 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 {"minVersion":"1.0.24"} 2026-08-14T22:10:05Z 2026-09-06T01:55:04Z v2.1.232 to v2.1.261
anonymous no longer carried 2026-08-19T04:20:14Z 2026-08-19T04:20:14Z v2.1.233
anonymous {"minVersion":"1.0.24"} 2026-08-14T22:10:05Z 2026-08-19T03:45:04Z v2.1.232 to v2.1.233

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, 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.