A new system-prompt section, opus5_reduced_delegation, adds guidance text for Opus-class models. It's skipped if that guidance is already present in a cached memory value.
Names in the bundleopus5_reduced_delegation
Feature flag
tengu_slate_bittern Not enough to sayNothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.
This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.257: on
These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.
Read once, for one account on one subscription tier, against v2.1.257. It isn't a statement about your account. What a flag value here can and cannot tell you
One source agreesOne thing we can check says the same as this entry.
The name it cites is new in this build
New in this build: tengu_slate_bittern