tengu_plan_mode_interview_phase
A Claude Code feature flag, read out of the shipped bundle. It was in the build from v2.1.138 and was gone by v2.1.145.
Default false. Turns on the iterative plan mode workflow: the full plan mode reminder uses an ## Iterative Planning Workflow section in place of the 5-phase workflow, the sparse reminder says Follow iterative workflow: explore codebase, interview user, write to plan incrementally., the EnterPlanMode tool description drops one section, and its result adds DO NOT write or edit any files except the plan file. CLAUDE_CODE_PLAN_MODE_INTERVIEW_PHASE set to a true value forces it on and a false value forces it off.
Not Anthropic's. Written by Claude Opus 5.5 from reading the v2.1.144 bundle, and it can be wrong.
In the changelogs
0No changelog entry here has ever named it. That is a statement about what has been written, not about the name: it has been in the build since v2.1.138 without anybody writing a line about it.
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
0No 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.
Presence across releases
2Build by build
149One 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.