What probably matters to youSection of the release
A new environment variable, CLAUDE_CODE_SUBAGENT_MODEL_FORCE, forces the Task tool to ignore a per-call model override for subagents/workflow agents. When set, the model parameter is stripped from the Task tool schema (n.omit({ model: !0 })), and workflow agent model requests are dropped with a logged message.
The in-tool Workflow authoring reference also checks CLAUDE_CODE_SUBAGENT_MODEL_FORCE: when set, it omits the model field from the documented agent() opts and drops the guidance text about setting model overrides in phase() entries and agent() calls, since a forced subagent model makes that option moot.
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Confirmed sinceAnthropic's documentation has since written up CLAUDE_CODE_SUBAGENT_MODEL_FORCE, on Model configuration.| `CLAUDE_CODE_SUBAGENT_MODEL` | The default model for [subagents](/docs/en/sub-agents#choose-a-model), [agent team](/docs/en/agent-teams#specify-teammates-and-models) teammates, and [workflow](/docs/en/workflows) agents that aren't assign…model-configsee the edit
How sure we are
Two sources agreeTwo things we can check say the same as this entry.
Anthropic's documentation agreesAnthropic's documentation has since written up CLAUDE_CODE_SUBAGENT_MODEL_FORCE, on Model configuration.
Anthropic's release notes agreeAdded CLAUDE_CODE_SUBAGENT_MODEL_FORCE to apply CLAUDE_CODE_SUBAGENT_MODEL (or the main model) to every subagent, ignoring per-spawn and…
The name it cites is new in this buildNew in this build: CLAUDE_CODE_SUBAGENT_MODEL_FORCE
