Placeholder MCP tool objects are built only behind a flag defaulting false plus a control-channel condition.
A stand-in tool object can be built for an MCP tool that is no longer connected, purely so past transcript entries display a proper ${t} - ${r} (MCP) name and result instead of a blank. It can never be called: every entry point throws. Built only when the tengu_violin_wood flag is on, whose fallback is false, and a remote/control-channel condition also holds, so it is inert in this build.
- Result text is stripped of OSC-8 terminal hyperlinks, other escape sequences and control characters before display.
- Calling one yields
Display-only MCP tool invoked \u2014 it exists only for transcript rendering.
Display-only MCP tool invoked \u2014 it exists only for transcript rendering
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
tengu_violin_wood Off in both readingsThe flag server returned off for the account this site reads and for the anonymous baseline. A reading of off cannot rule out a rollout these two readings sit outside of.
This account: off · anonymous baseline: off · compiled default in v2.1.239: off
Read once, for one account on one subscription tier, against v2.1.239. It isn't a statement about your account. What a flag value here can and cannot tell you
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.
A reading is one sample. Claude Code evaluates its flags remotely, so no client sees the targeting rule behind a value and this says nothing about your account.