tengu_carved_slate

A Claude Code feature flag, read out of the shipped bundle. It was in the build from v2.1.251 and was gone by v2.1.268.

Releases whose published page names tengu_carved_slate.

1. v2.1.265 8 Sep 2026
   Static system prompt mode (tengu_carved_slate) strips dynamic content from agent prompts when on

   A new staticSystemPromptEnabled flag can strip dynamic content from agent system prompts

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

2. v2.1.252 31 Aug 2026
   Incremental CLAUDE.md / tool-description context diffing ('instructions' attachments)

   Claude Code now only re-sends changed CLAUDE.md/instruction files instead of the whole block each turn, saving tokens.

   gate cited by this entry

3. v2.1.252 31 Aug 2026
   New "instructionFiles" context channel, gated behind carved-slate flag

   A separate instruction-files context channel exists but is off by default, part of a static system prompt rework.

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

4. v2.1.252 31 Aug 2026
   Context/cost breakdown now counts tool descriptions from a recorded prompt snapshot

   Context/cost breakdowns like /context now reuse the exact tool description text actually sent, for accuracy.

   gate cited by this entry

5. v2.1.252 31 Aug 2026
   Scratchpad directory: a new per-session temp-file location announced to the model

   Claude may soon be told to use a per-session scratchpad directory for temp files instead of /tmp.

   gate cited by this entry

6. v2.1.252 31 Aug 2026
   Scratchpad directory tracked in environment-change diffs and telemetry schema

   The scratchpad directory is now tracked in environment-change diffs and telemetry like other environment fields.

   gate cited by this entry

7. v2.1.252 31 Aug 2026
   claudeMd now explicitly emitted as empty string under carved-slate mode

   Under an experimental mode, empty CLAUDE.md content is now sent as an explicit empty string to keep prompt caching stable.

   gate cited by this entry

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.

No release's published evidence quotes this name. The ledger indexes the Evidence lines of every changelog on this site, so this says nobody here has ever quoted it; it says nothing about how old the name is.

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.