tengu_binary_lollipop
A Claude Code feature flag, read out of the shipped bundle. It has been in the build since v2.1.290, including the newest one read.
Claude Code now contains the name of a new server-controlled switch, but nothing yet shows what it controls
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.290.
In the changelogs
1Releases whose published page names tengu_binary_lollipop.
-
v2.1.290
New remote switch name with no visible feature behind it
Claude Code now contains the name of a new server-controlled switch, but nothing yet shows what it controls
found in this entry's text
Gate readings
0No release here has a gate table behind it for this flag. Most published releases have none at all: the readings exist only for versions the pipeline captured flag state on.
First cited
1The earliest release whose published evidence quoted tengu_binary_lollipop was v2.1.290, 5 Oct 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.
Presence across releases
1Build by build
6One 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.