tengu_stellar_drift
A Claude Code feature flag, read out of the shipped bundle. It has been in the build since v2.1.257, including the newest one read.
Two transcript debugging aids, raw tool inputs and exact wire block order, are computed but each sits behind its own gate.
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.257.
In the changelogs
2Releases whose published page names tengu_stellar_drift.
-
v2.1.257
Wire-format echo debugging fields (tool inputs + block order) are built but flag-gated off
Two transcript debugging aids, raw tool inputs and exact wire block order, are computed but each sits behind its own gate.
gate cited by this entry
-
v2.1.257
New gated experiment: tengu_stellar_drift
A new capability flag can be forced on with an env var, with no stated effect.
found in this entry's text, gate cited by this entry
Gate readings
0No release here has a gate table behind it for this flag. Most published releases have none at all: the readings exist only for versions the pipeline captured flag state on.
Flag server, over time
10| Read as | Reading | From | Until | Version installed |
|---|---|---|---|---|
| this account | on | 2026-09-12T19:15:05Z | 2026-09-23T09:25:04Z | v2.1.269 to v2.1.280 |
| anonymous | on | 2026-09-11T19:55:04Z | 2026-09-23T09:25:04Z | v2.1.269 to v2.1.280 |
| this account | off | 2026-09-12T19:13:54Z | 2026-09-12T19:13:54Z | v2.1.270 |
| this account | on | 2026-09-11T21:00:07Z | 2026-09-12T18:15:04Z | v2.1.269 |
| this account | off | 2026-09-11T20:55:57Z | 2026-09-11T20:55:57Z | v2.1.269 |
| this account | on | 2026-09-10T22:50:04Z | 2026-09-11T20:15:07Z | v2.1.268 to v2.1.269 |
| anonymous | off | 2026-09-08T21:35:04Z | 2026-09-11T19:35:04Z | v2.1.265 to v2.1.269 |
| this account | off | 2026-09-10T21:47:12Z | 2026-09-10T21:47:12Z | v2.1.268 |
| this account | no longer carried | 2026-09-10T21:46:45Z | 2026-09-10T21:46:45Z | v2.1.268 |
| this account | off | 2026-09-08T21:55:04Z | 2026-09-10T17:40:05Z | v2.1.265 to v2.1.267 |
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
0No release's published evidence quotes this name. The ledger indexes the Evidence lines of every changelog on this site, so this says nobody here has ever quoted it; it says nothing about how old the name is.
Presence across releases
1Build by build
21One 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.