Claude Code v2.1.218 Fixes /code-review, MCP Auth, Windows Path Corruption

Claude Code v2.1.218 is out with a laundry list of fixes and improvements. The headline change: /code-review now runs as a background subagent, keeping your main conversation clean and allowing stacked slash commands to target the review context.

Key Fixes

• Windows path corruption fixed: Paths with \u segments (e.g., C:\Users\unicorn) were being misinterpreted as CJK unicode escapes, making files inaccessible. No longer.
• Left arrow accidental data loss: Pressing left arrow after editing now asks for confirmation; Esc in the agent view returns to the backgrounded conversation.
• MCP connectivity: claude mcp list and /mcp now show HTTP status and error text when a server fails to connect. Hidden leading/trailing whitespace in MCP config values also triggers a warning.
• Multi-line paste with j: Terminals that encode pasted newlines as Ctrl+J no longer collapse multi-line pastes into a single line with j in place of newlines.
• /ultrareview with descriptive args: Calling /ultrareview review my auth changes now works correctly, running a review of the current branch with the text applied as a note.
• /code-review ultra in non-interactive: No longer silently falls back to local review; now launches the cloud review as expected.

Improvements

• Auto mode refinements: Dangerous-rm, background-& and suspicious-Windows-path checks no longer open permission dialogs—the auto-mode classifier handles them. Plan mode with auto similarly delegates bash read-only analysis to the classifier instead of prompting.
• /deep-research manual only: Claude will no longer autonomously start a deep research session; it must be invoked manually.
• Trust dialogs: Now name the repository root the grant covers.

Accessibility & Reliability

• Screen-reader announcements for word/line deletions in --ax-screen-reader mode. VoiceOver no longer reads "new line" for typed spaces.
• Fix for deeply nested watched directory deletions causing stack-overflow crashes.
• Monotonic clock timers to prevent negative turn durations after system clock adjustments.
• Resume sessions no longer crash from malformed delta attachments.
• Fork-session lineage preserved after compaction in headless/SDK sessions.

Other Notables

• Bedrock wizard: Assumes-role profiles in partitioned AWS regions and proxy-only networks now pass verification.
• Gateway metering: Bedrock application-inference-profile ARNs are priced at the configured model's rates.
• Prompt history: Race conditions causing dropped or duplicated history entries resolved.
• Retry loop fix: Identical doomed requests after context-overflow with large thinking budget no longer loop. Ctrl+B backgrounding gets the same caps as other paths.