tengu_lantern_wick_mode
A Claude Code feature flag, read out of the shipped bundle. It has been in the build since v2.1.227, including the newest one read.
Claude could be nudged to wrap up or checkpoint during your usage-limit grace window, but nothing fires.
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.227.
In the changelogs
4Releases whose published page names tengu_lantern_wick_mode.
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v2.1.284
The near-limit usage notice now counts as a wrap-up note
Near a usage limit, Claude Code now treats its near-limit notice like the wrap-up reminder when deciding what to tell the model next
gate cited by this entry
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v2.1.277
Usage-limit "wrap-up" reminder injection, gated off by default
A new 'wrap up your work' reminder can be injected near usage limits, currently gated off
gate cited by this entry
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v2.1.227
Wrap-up nudge during the rate-limit grace window
Claude could be nudged to wrap up or checkpoint during your usage-limit grace window, but nothing fires.
gate cited by this entry, found in this entry's text
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v2.1.227
Usage-limit grace window can ask for next steps
The grace-window nudge can now ask Claude to checkpoint and list remaining work, but stays off.
gate cited by this entry, found in this entry's text
Gate readings
3| Release | Resolved | This account | Anonymous | Compiled default |
|---|---|---|---|---|
| v2.1.284 read on another version | Not enough to say | no value returned | no value returned | not a boolean we can read |
| v2.1.277 read on another version | Not enough to say | no value returned | no value returned | not a boolean we can read |
| v2.1.227 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
12| Read as | Reading | From | Until | Version installed |
|---|---|---|---|---|
| anonymous | "off" | 2026-10-17T05:30:04Z | 2026-10-22T17:35:05Z | v2.1.302 to v2.1.308 |
| this account | "off" | 2026-09-10T21:47:12Z | 2026-10-22T17:35:05Z | v2.1.268 to v2.1.308 |
| anonymous | no longer carried | 2026-10-17T05:25:57Z | 2026-10-17T05:25:57Z | v2.1.302 |
| anonymous | "off" | 2026-08-19T04:25:04Z | 2026-10-17T05:10:04Z | v2.1.233 to v2.1.302 |
| this account | no longer carried | 2026-09-10T21:46:45Z | 2026-09-10T21:46:45Z | v2.1.268 |
| this account | "off" | 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 | "off" | 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 | "off" | 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 | "off" | 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.
First cited
1The earliest release whose published evidence quoted tengu_lantern_wick_mode was v2.1.227, 10 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 below.
Presence across releases
5Build by build
70One 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.