v2.1.154

What's changed

• Opus 4.8 is here! Now defaults to high effort · /effort xhigh for your hardest tasks


• Introducing dynamic workflows: ask Claude to create a workflow and it orchestrates work across tens to hundreds of agents in the background, so you can take on larger, more complex tasks. Run /workflows to view your runs


• Fast mode on Opus 4.8 is now available at a fraction of its previous cost: 2x the standard rate for 2.5x the speed


• The lean system prompt is now the default for all models except Haiku, Sonnet, and Opus 4.7 and earlier


• Claude now reserves the multiple-choice question prompt for decisions it genuinely cannot make itself, instead of asking when it already has enough context to proceed


• /simplify now runs a cleanup-only review (reuse, simplification, efficiency, altitude) and applies the fixes, instead of running the full /code-review --fix bug-hunting review


• Renamed the /effort slider labels from "Speed"/"Intelligence" to "Faster"/"Smarter" for clarity


• claude agents: type ! <command> to run a shell command as a background session you can attach to and detach from. Also available as claude --bg --exec '<command>'


• claude agents: /logout now signs you out instead of being sent to a background session


• ←← to open the agents view now works on Bedrock, Vertex, Foundry, and with telemetry disabled


• Claude in Chrome: pick which connected browser to use via /chrome → "Select browser…", or in-chat when a browser action runs with multiple connected


• Plugins can now declare defaultEnabled: false in plugin.json or a marketplace entry; enable them with /plugin or claude plugin enable. Dependencies of enabled plugins are still enabled automatically


• The /plugin Discover tab now pins plugins whose relevance signals match the current directory with a "suggested for this directory" annotation


• Streaming tool execution is now always enabled, including when telemetry is disabled or on Bedrock/Vertex/Foundry (previously behind a feature flag)


• Stdio MCP server subprocesses now receive CLAUDE_CODE_SESSION_ID and CLAUDECODE=1 in their environment


• claude mcp list/get now show unapproved .mcp.json servers as ⏸ Pending approval instead of auto-approving and connecting when output is piped


• /remote-control autocomplete now shows "Disconnect Remote Control" when Remote Control is already active


• Added Claude Opus 4.8 support and 4.7 → 4.8 migration guidance to the /claude-api skill


• Deprecated CLAUDE_CODE_OPUS_4_6_FAST_MODE_OVERRIDE (will be removed on 06/01). To use fast mode on Opus 4.6, switch with /model claude-opus-4-6[1m] and then /fast on


• Improved the auto-mode classifier's detection of data exfiltration, particularly bulk transfers of repository contents


• Fixed rm -rf $HOME not being blocked as a dangerous path when HOME has a trailing slash


• Fixed $TMPDIR resolving to different directories in sandboxed vs unsandboxed Bash commands within the same session


• Fixed unreadable highlighted-row text in claude agents when the Claude Code theme doesn't match the terminal background


• Fixed background-agent completion notifications triggering premature "out of context" behavior on some 1M-context models


• Fixed background-session classifier losing the user's goal when a scheduled /command fires


• Fixed pinned background sessions respawning every minute after a Claude Code update, causing repeated agent-start notifications and process churn at idle


• Fixed background sessions stuck at "blocked", "running", or "working" not retiring after the idle grace period


• Fixed subagents in background sessions bypassing the worktree-isolation guard and writing to the shared checkout


• Fixed orphaned claude --bg-pty-host processes spinning at 100% CPU after the daemon exits on macOS


• Fixed number key shortcuts not working for options shown below the divider in option dialogs


• Fixed worktree.baseRef: "head" resolving to the main checkout's HEAD instead of the current worktree's HEAD when spawning subagents or calling EnterWorktree from inside a linked worktree


• Fixed a stray leading space on wrapped lines when the previous line ended exactly at the terminal width


• Fixed intermittent terminal rendering corruption in VS Code by capping the number of distinct colors the thinking spinner produces


• Fixed plan file names including [Image #N] / [Pasted text #N] placeholders when a plan-mode prompt starts with pasted images or text


• Fixed a phantom expand/click affordance on colored tool output: short ANSI-colored lines that fit on screen no longer show a "ctrl+o to expand" hint


• Fixed a single invalid allowedMcpServers/deniedMcpServers entry in managed settings discarding all managed-settings policy; the bad entry is now dropped with a claude doctor warning


• Fixed API 400 errors on models that don't support the effort parameter when CLAUDE_CODE_ALWAYS_ENABLE_EFFORT is set


• Windows: Fixed update failures caused by claude.exe being in use showing a generic error instead of telling you to close other sessions and retry


• Removed the stale "& for background" hint from the shortcuts help panel


• [VSCode] Auto mode no longer requires the bypass-permissions setting to appear in the mode picker, and a dismissable notice on the new-session screen explains auto mode the first time it's active


• Fixed the task panel below the prompt showing a stray unselectable "main" row when only a workflow is running


• Fixed /mcp tools list and tool detail rendering when MCP servers have long or multi-line tool names or long descriptions


• Fixed the /model picker not showing fast mode pricing on the Default option for API (pay-as-you-go) users when fast mode is on


• Fixed auto mode incorrectly blocking actions with "could not evaluate this action" when the safety classifier ran out of output tokens while reasoning