What it is
MCP config building gets a new caching layer, currently unread/off
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.265.
Presence across releases
2Build by build
15One 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
2The earliest release whose published evidence quoted tengu_cobalt_plinth_loquat was v2.1.265, 8 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 |
|---|---|---|---|---|
| v2.1.265 | 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.
Names beside it
Every feature flag in the inventory starting tengu_cobalt_plinth, up to twelve of them.
tengu_cobalt_plinthPR review artifact pages can show a pinned button that approves the pull request from your GitHub account. v2.1.172
tengu_cobalt_plinth_alderClaude can now read back a published artifact's contents; browsing, multi-file publishing and deletion are built but off. v2.1.239
tengu_cobalt_plinth_aspenThe preview browser is locked to the local server and refuses to run if the lock fails. v2.1.247
tengu_cobalt_plinth_brackenYou could start a private artifact from a published template, but two server switches keep it shut here. v2.1.216
tengu_cobalt_plinth_bryonyNo description from anybody. v2.1.273
tengu_cobalt_plinth_burnetArtifact comment and subscription operations can each be switched on separately from the server. v2.1.268
tengu_cobalt_plinth_campionPublish checks could warn about page thumbnails, but the experiment is off. v2.1.251
tengu_cobalt_plinth_comfreyA new flag affects relay routing when reading published artifact files. v2.1.261
tengu_cobalt_plinth_damsonThe artifact tool's flat verbs are mapped to a canonical action shape, with a gate deciding which toolset is active. v2.1.257
tengu_cobalt_plinth_datavizThe chart skill hint now only appears if the dataviz skill is actually installed. v2.1.198
tengu_cobalt_plinth_directArtifact availability now hinges on one gate, and direct upload kicks in for create paths. v2.1.172
tengu_cobalt_plinth_fennelBot-driven sessions no longer relay artifact requests; they go direct or not at all. v2.1.247
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.