Claude Code's built-in Task tools vanish server-side

A GitHub bug report describes a failure in Claude Code 2.1.217 and 2.1.218 on macOS arm64: after the TodoWrite-to-Task migration, the built-in task tools sometimes don't register at all. A ToolSearch for TaskList, TaskCreate, TaskUpdate, and TaskGet came back empty, while 189 other deferred tools were available.

In one 2.1.218 session, four tools loaded and worked at first, then minutes later a system notice said they'd been turned off because "their MCP server disconnected." TaskStop and TaskOutput stuck around.

The author pulled the binaries for both versions: the Task gating code is identical, and neither the tengu_vellum_ash flag nor the CLAUDE_CODE_ENABLE_TASKS variable disabled anything locally. His conclusion is that exactly those four tools sharing one gate point to flag or registry instability on the server side.