What it is
A new gate, tengu_quiet_lantern, controls whether the server classifier falls back to local when unsupported
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.278.
Presence across releases
1Build by build
1One 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.
First cited
1The earliest release whose published evidence quoted tengu_quiet_lantern was v2.1.278, 19 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.
Gate readings
1| Release | Resolved | This account | Anonymous | Compiled default |
|---|---|---|---|---|
| v2.1.278 read on another version | Not enough to say | no value returned | no value returned | on |
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.
Names beside it
Every feature flag in the inventory starting tengu_quiet, up to twelve of them.
tengu_quiet_dolphinThe /diff panel is now prototyped internally as a plugin pane rather than built-in UI never mined
tengu_quiet_harborNo description from anybody. v2.1.138
tengu_quiet_heronContinuing a server-side conversation thread can now skip resending the system prompt and tools list, with a fallback if the server disagrees v2.1.269
tengu_quiet_hollowNo description from anybody. never mined
tengu_quiet_slate_wrenNo description from anybody. v2.1.138
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.