tengu_stone_shell

A Claude Code feature flag, read out of the shipped bundle. It was in the build from v2.1.212 and was gone by v2.1.286.

Releases whose published page names tengu_stone_shell.

1. v2.1.286 30 Sep 2026
   A server-controlled switch is now locked off in code

   A check that used to ask the server whether to turn on a feature now always answers off, so no server setting can switch it on

   gate cited by this entry, found in this entry's text

2. v2.1.238 20 Aug 2026
   The memory-tools gate was renamed, so everyone is back on file-based memory

   The memory-tools switch was renamed, resetting any rollout, so everyone is back on file-based memory.

   gate cited by this entry, found in this entry's text

3. v2.1.232 13 Aug 2026
   Two feature decisions moved onto the shared process config object

   The memory prompt variant and the skill-suggestion rollout are now fields on the process config.

   gate cited by this entry, found in this entry's text

4. v2.1.224 7 Aug 2026
   An auto-generated index of your memory files

   Claude can auto-generate an index of your memory files and feed it in as a source.

   gate cited by this entry, found in this entry's text

5. v2.1.219 24 Jul 2026
   Rewritten memory system prompt

   Rewritten memory rules would make Claude save corrections and environment quirks immediately, before replying.

   gate cited by this entry, found in this entry's text

6. v2.1.219 24 Jul 2026
   Memory subagent's delete permission narrowed

   The memory cleanup agent could only delete plain memory files, never anything with flags or outside the folder.

   gate cited by this entry, found in this entry's text

7. v2.1.219 24 Jul 2026
   Memory truncation warning now covers ordinary memory files

   Oversize memory warnings would finally say something sensible about ordinary files, not just index entries.

   gate cited by this entry, found in this entry's text

8. v2.1.219 24 Jul 2026
   Compact recall/remember summaries in the transcript

   Memory recall notes could show as a compact grouped line in normal sessions, but that view is off.

   gate cited by this entry, found in this entry's text

9. v2.1.219 24 Jul 2026
   Pinned memories are injected into the session

   Adding pinned: true to a memory file's frontmatter would apply it to every session automatically.

   gate cited by this entry, found in this entry's text

10. v2.1.212 16 Jul 2026
    Persistent File-Based Memory (tengu_stone_shell) [Gradual Rollout]

    gate cited by this entry, found in this entry's text

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.

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.

The earliest release whose published evidence quoted tengu_stone_shell was v2.1.212, 16 Jul 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.

One 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.