Auto-mode subagents reporting back via SubagentHandback moves from an off-by-default flag to on-by-default in code
The SubagentHandback mechanism requires a subagent running in "auto" mode to deliver its final report by explicitly calling a SubagentHandback tool, rather than just ending its turn with plain text; when required, plain trailing text from the subagent isn't delivered back to whatever called it. The function controlling whether this is required now defaults to enabled in code, though it can still be overridden with the CLAUDE_CODE_SENDMESSAGE_HANDBACK environment variable.
This changes the code-level default for how auto-mode subagents are expected to hand back results, moving from opt-in to opt-out, though whether it's actually active depends on the tengu_lively_waffle flag setting for a given account.
tengu_lively_waffle On for this account, and not off by defaultThe flag server returned on for the one account this site reads, and nothing in this release compiles it off by default. The compiled default is shown below, and says which it is when we cannot read one: a fifth of gates compile in a string or a number rather than on or off, and most published releases have no gate table behind them at all. No client can see what the server returns for your account.
This account: on · anonymous baseline: on · compiled default in v2.1.271: 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 v2.1.271. 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.