Claude Code v2.1.302: Fork Subagents On by Default, Pick the Auto Mode Classifier Model
What is it?
Fork subagents are now on by default in claude -p, the Agent SDK, the desktop app and VS Code. To turn them off, set this environment variable:
CLAUDE_CODE_FORK_SUBAGENT=0You can choose the model auto mode uses to classify risky commands with CLAUDE_CODE_AUTO_MODE_MODEL. On third-party providers, sessions with no permission mode set now start in default.
Why does it matter?
If you run claude -p in CI or scripts, subagent behavior and token use may change after the update. On a third-party provider, check whether your permission mode shifts to default. A prompt cache miss after ToolSearch loads a tool is also fixed.
Maturity
GAStable release. Behavior changes for unattended runs and third-party providers, so test first.
How to track it
- Next release: watch the Claude Code changelog for follow-up fixes to fork subagents.
- Usage: compare token use of your
claude -pjobs before and after the update. - Permissions: check whether the docs add guidance on permission modes for third-party providers.