Claude Code 2.1.221 - リリースノート

日本語サマリー

以下は Claude Code 2.1.221 のリリースノートの要約です。

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主な変更点と修正内容

• 【重要】セキュリティ・権限チェックのバイパスを修正
  • Bash ツールで zsh の [[ ]] 内に隠されたコマンドが実行される問題を修正し、該当コマンドには権限プロンプトを要求するようにしました。
  • Windows 環境の PowerShell において、クォート文字を含むパスの権限チェックが誤作動する問題を修正しました。
• 新機能: Focus view の追加
  • ツールのアクティビティを非表示にし、展開可能なサマリーに切り替えられる Focus view を VSCode に追加しました（Ctrl+Alt+F で切り替え）。
• 新機能: クレデンシャルファイルのマスキング (mode: "mask")
  • Linux/WSL 環境の sandbox にて、コマンドにはダミーデータを読ませて外部送信時に実際の値を差し替える mask モードを追加しました。
• 新機能: プロンプト監査機能
  • claude-api skill に、古いモデル向けに書かれたパターンを監査する prompt-audit サブコマンドを追加しました。
• 各種不具合の修正
  • print mode (-p) で --mcp-config の MCP サーバーが最初のターン前に接続されない問題や、thinking のトグルが効かない問題を修正しました。
  • Esc キーでプロンプトを取り消した際、@ でメンションしたファイルが消える問題を修正しました。
  • xhigh/max エフォート時の WebSearch の 400 エラーや、sandbox 配下での TLS エラーを修正しました。
  • Vim mode の挙動（yank registerの保持など）や、各種わかりにくいエラーメッセージを改善しました。
• 機能改善と最適化
  • Google Vertex AI でのツール検索を Claude 4.5 世代以降で再有効化しました。
  • auto mode の権限チェックのキャッシュ効率を改善し、プロンプトキャッシュのコストを削減しました。
  • Windows の起動プロセスを改善し、powershell.exe の起動に依存しないようにしました。
• 仕様変更・アップデート
  • バックグラウンドセッションが、タスクに必要な場合のみドラフト PR を作成するように変更しました。
  • /fork で分岐したセッションは、元のチェックアウト環境ではなく新しい worktree を作成するように変更しました。
  • /status コマンドがセッションの種別（interactive やバックグラウンドジョブなど）を表示するようになりました。
  • 絵文字のオートコンプリートが :thumbsup: などの代替ショートコードに対応しました。

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原文（Release Notes）

What's changed

• [VSCode] Added Focus view: a chat-menu toggle that hides tool activity behind an expandable per-turn summary with a live running-tool indicator, toggled with Ctrl+Alt+F or the "Claude Code: Toggle Focus view" command
• Added mode: "mask" for sandbox credential files on Linux and WSL — sandboxed commands read a sentinel copy (the whole file, or just the spans captured by an extract regex) while the sandbox proxy substitutes the real value on egress; on macOS file masking falls back to deny
• Added warnings to claude plugin validate when a marketplace or plugin name would be rejected by Claude Desktop's managed marketplace sync
• Added a prompt-audit subcommand to the claude-api skill for auditing prompts and tool descriptions for patterns written for older models
• Fixed a Bash tool permission-check bypass where zsh could execute hidden commands in [[ ]] regex conditionals; affected commands now prompt for permission
• Fixed PowerShell permission checks mishandling paths containing quote characters on Windows; such paths now prompt for approval
• Fixed the thinking toggle having no effect for the rest of a session that started with thinking off; disabling an MCP server mid-connect no longer silently reverts
• Fixed MCP servers from --mcp-config not being connected before the first turn in print mode (-p), which made the model emit tool calls as literal text
• Fixed @-mentioned files being silently dropped when pressing Esc to retract a prompt and resubmitting it
• Fixed a crash when preparing API requests for SDK MCP tools named after built-in object properties such as constructor
• Fixed WebSearch failing with a 400 error at effort xhigh/max when thinking is disabled
• Fixed sandboxed large uploads failing with TLS errors through the sandbox proxy
• Fixed Team and Enterprise spend-limit message incorrectly blaming the org's monthly limit instead of your individual spend limit
• Fixed Bedrock authentication with AWS SSO named profiles failing in desktop-managed sessions on Windows machines that set a stray HOME environment variable
• Fixed CLAUDE_CODE_RESUME_INTERRUPTED_TURN=0 not disabling interrupted-turn auto-resume; falsy values are now honored
• Fixed a rare wake-from-sleep race where two Claude Code processes could both refresh the same MCP connector or WIF OAuth token at once, forcing re-authentication
• Fixed renaming a session from Claude Code Desktop or claude.ai not updating the CLI's session name; session names from every rename surface are now sanitized
• Fixed plugin- and org-delivered skills named after terminal-only built-ins (e.g. /help, /feedback) being un-invocable in non-interactive sessions
• Fixed the "Plugins changed" notification lingering after plugins were reloaded instead of clearing
• Fixed Vim mode: the yank register now survives dialogs, history search, and the transcript view instead of being silently emptied
• Fixed Vim mode: undoing back to an empty prompt now arms the "press ← again" confirm before returning to the agent view
• Improved tool search on Google Vertex AI: re-enabled for Claude 4.5-generation and newer models
• Improved auto mode: permission checks for parallel tool calls are now cache-efficient, and switching modes while a check is pending reliably prompts instead of applying the stale result
• Reduced prompt-cache costs for auto-mode permission checks by reusing the cached conversation prefix across decisions
• Improved Stats panel to count cache tokens in its token totals, with a breakdown by input, output, cache read, and cache write
• Improved /ultrareview error messages when a repo shares no history with its base: a checkout with no branches is now refused up front with advice to create one, and refusal hints no longer suggest git fetch --unshallow on clones that are already complete
• Improved Windows startup: process creation times are now read via a native kernel32 call instead of spawning PowerShell, so endpoint security tools that gate powershell.exe no longer prompt
• Changed background sessions to commit and push to preserve work, open a draft PR only when the task calls for one, follow your CLAUDE.md git instructions, and always end by reporting where the work lives
• Changed /plugin install to refresh a stale marketplace catalog and retry before reporting a plugin not found
• Changed plugins installed from /plugin to activate immediately when safe, instead of always requiring /reload-plugins
• Changed plugins to accept "." as a skills path, and the root-level SKILL.md validation error now suggests using the plugin root
• Changed /status to show the session kind: interactive, or a background job that is attached or unattended
• Changed emoji autocomplete to accept common alternate shortcodes like :thumbsup:, :thumbsdown:, and :love:
• Changed sessions forked with /fork to create a new worktree of their own instead of working in the original session's checkout
• Changed Claude in Chrome to close the browser tabs it opens once it no longer needs them
• Changed fast mode to report on the stream when usage credits run out mid-session, instead of failing silently
• Changed Monitor: a watch that exits without producing any output now says so instead of reporting "stream ended"
• Changed the Gateway model field validation: non-string values are rejected with a 400 instead of being forwarded
• Removed the repeated "Permission mode changed while the auto-mode classifier call was queued" notice from approval prompts