tengu_umber_stile
A Claude Code feature flag, read out of the shipped bundle. It has been in the build since v2.1.265, including the newest one read.
A new str_replace write action for the artifact database is built but not yet exposed to users
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.265.
In the changelogs
5Releases whose published page names tengu_umber_stile.
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v2.1.269
Artifact str_replace writes gated behind a new require-version check, off by default
Artifact edits can now require a version match before writing, gated off by default
gate cited by this entry, found in this entry's text
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v2.1.265
Artifact DB str_replace action is built but flagged off
A new str_replace write action for the artifact database is built but not yet exposed to users
gate cited by this entry
-
v2.1.265
Artifact database gains str_replace, optimistic concurrency, batch admin/interact levels
Artifact database tool adds find-and-replace edits, version-conflict protection, and admin-level access
gate cited by this entry
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v2.1.265
Artifact-database str_replace edit op, gated off by default
Artifact database gains a targeted str_replace edit operation, currently gated off
gate cited by this entry
-
v2.1.265
Artifact-database write gains a string-replace op and optimistic versioning
Artifact database writes gain a string-replace operation and version-checked writes
gate cited by this entry
Gate readings
2| Release | Resolved | This account | Anonymous | Compiled default |
|---|---|---|---|---|
| v2.1.269 | Off by default, switched on for this account | on | on | off |
| v2.1.265 | Not enough to say | no value returned | no value returned | 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
21| Read as | Reading | From | Until | Version installed |
|---|---|---|---|---|
| this account | on | 2026-11-02T13:05:04Z | 2026-11-12T05:55:04Z | v2.1.316 to v2.1.322 |
| anonymous | on | 2026-10-17T05:30:04Z | 2026-11-12T05:55:04Z | v2.1.302 to v2.1.322 |
| this account | off | 2026-11-02T12:55:05Z | 2026-11-02T12:55:05Z | v2.1.316 |
| this account | on | 2026-11-01T20:45:05Z | 2026-11-02T12:40:07Z | v2.1.316 |
| this account | off | 2026-11-01T20:40:05Z | 2026-11-01T20:40:05Z | v2.1.316 |
| this account | on | 2026-11-01T20:25:04Z | 2026-11-01T20:30:06Z | v2.1.316 |
| this account | off | 2026-11-01T20:20:05Z | 2026-11-01T20:20:05Z | v2.1.316 |
| this account | on | 2026-10-07T18:00:12Z | 2026-11-01T19:30:06Z | v2.1.292 to v2.1.316 |
| anonymous | no longer carried | 2026-10-17T05:25:57Z | 2026-10-17T05:25:57Z | v2.1.302 |
| anonymous | on | 2026-09-10T21:46:45Z | 2026-10-17T05:10:04Z | v2.1.268 to v2.1.302 |
| this account | off | 2026-10-07T17:59:34Z | 2026-10-07T17:59:34Z | v2.1.293 |
| this account | on | 2026-09-11T02:50:28Z | 2026-10-07T17:10:05Z | v2.1.268 to v2.1.292 |
| this account | off | 2026-09-11T02:35:04Z | 2026-09-11T02:35:04Z | v2.1.268 |
| this account | on | 2026-09-10T22:50:04Z | 2026-09-11T01:50:04Z | v2.1.268 |
| 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 | 2026-09-09T15:25:04Z | 2026-09-10T17:40:05Z | v2.1.266 to v2.1.267 |
| anonymous | off | 2026-09-09T15:15:04Z | 2026-09-10T17:40:05Z | v2.1.266 to v2.1.267 |
| this account | on | 2026-09-08T21:55:04Z | 2026-09-09T15:15:04Z | v2.1.265 to v2.1.266 |
| anonymous | on | 2026-09-08T21:40:04Z | 2026-09-09T10:05:06Z | v2.1.265 to v2.1.266 |
| anonymous | off | 2026-09-08T21:35:04Z | 2026-09-08T21:35:04Z | v2.1.265 |
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
1The earliest release whose published evidence quoted tengu_umber_stile was v2.1.269, 11 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
1Build by build
53One 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.