Fork subagents on by default
Claude Code v2.1.302 turns fork subagents on in the Agent SDK and VS Code, and standalone Claude Design closes December 14
- Now on in
- claude -p, the Agent SDK, the desktop app and VS Code
- Already on in
- the terminal
- Never offered by
- claude mcp serve
Fork subagents are now on by default in claude -p, the Agent SDK, the Claude desktop app and VS Code, matching the terminal. Claude MCP serve never offers them.
Subagents run in the background
>The desktop app and VS Code always run subagents in the background
- Main conversation
- its subagents always run in the background, as in the terminal
- A subagent’s own Agent calls
- foreground by default in claude -p, the Agent SDK, the desktop app and VS Code
In the Claude desktop app and VS Code, the main conversation's subagents now always run in the background, as in the terminal. A subagent's own Agent calls run in the foreground by default.
Default permission mode
>claude -p and the Agent SDK start in default permission mode on third-party providers
- When
- no permission mode is set, with telemetry off or on a fresh install
- Still auto
- --permission-mode auto keeps auto mode
On a third-party provider, a claude -p or Agent SDK session with no permission mode set now starts in default mode, when telemetry is off or on a fresh install. Asking for auto mode explicitly still gets it.
Auto mode classifier model
>Choose the model behind the client-side auto mode classifier
CLAUDE_CODE_AUTO_MODE_MODEL
- Client-side auto mode
- the classifier uses the model you set
- Server-side auto mode
- keeps its model; a conversation too long for the safety check is now compacted
A new environment variable, CLAUDE_CODE_AUTO_MODE_MODEL, sets the model for auto mode's client-side classifier. Server-side auto mode keeps its own model, and now compacts an overlong conversation instead of denying every checked tool call.
Idle compaction toggle
>Turn idle compaction off or back on from /config
- /config
- a new Idle compaction row
- After an idle compaction
- the notice says how to turn it off
Claude Code's /config screen now has an Idle compaction row, so you can turn idle compaction off or back on. The notice shown after an idle compaction now tells you how to turn it off.
Standalone Claude Design closes
>Standalone Claude Design closes by December 14, 2026
- Closing
- claude.ai/design
- Notice shown in
- /design-sync and /design-login
Standalone Claude Design closes by December 14, 2026. Claude Code's /design-sync and /design-login commands now show that notice, so plan for it if your design work happens there.
Fixes you may have hit
>Fixed: huge images in Read, stopping during compaction, exFAT drives on Windows
- Read
- image sources over 128 MB are refused instead of loaded into memory
- Stopping a turn
- during compaction no longer ends in “Prompt is too long”
- Windows
- file writes work on exFAT and FAT32 drives
The Read tool now refuses image sources over 128 megabytes instead of loading them into memory. Stopping a turn during compaction no longer fails as too long. And Windows file writes work on exFAT and FAT32 drives.
The full changelog
Every change is in the Claude Code changelog
https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md
The Claude Code changelog on GitHub has the rest, including faster startup with many plugins and a long list of fixes for cloud sessions and Claude Tag.
