Claude Code v2.1.117、外部ビルドでのフォークサブエージェント機能を追加

What's changed

• Forked subagents can now be enabled on external builds by setting CLAUDE_CODE_FORK_SUBAGENT=1

• Agent frontmatter mcpServers are now loaded for main-thread agent sessions via --agent

• Improved /model: selections now persist across restarts even when the project pins a different model, and the startup header shows when the active model comes from a project or managed-settings pin

• The /resume command now offers to summarize stale, large sessions before re-reading them, matching the existing --resume behavior

• Faster startup when both local and claude.ai MCP servers are configured (concurrent connect now default)

• plugin install on an already-installed plugin now installs any missing dependencies instead of stopping at "already installed"

• Plugin dependency errors now say "not installed" with an install hint, and claude plugin marketplace add now auto-resolves missing dependencies from configured marketplaces

• Managed-settings blockedMarketplaces and strictKnownMarketplaces are now enforced on plugin install, update, refresh, and autoupdate

• Advisor Tool (experimental): dialog now carries an "experimental" label, learn-more link, and startup notification when enabled; sessions no longer get stuck with "Advisor tool result content could not be processed" errors on every prompt and /compact

• The cleanupPeriodDays retention sweep now also covers ~/.claude/tasks/, ~/.claude/shell-snapshots/, and ~/.claude/backups/

• OpenTelemetry: user_prompt events now include command_name and command_source for slash commands; cost.usage, token.usage, api_request, and api_error now include an effort attribute when the model supports effort levels. Custom/MCP command names are redacted unless OTEL_LOG_TOOL_DETAILS=1 is set

• Native builds on macOS and Linux: the Glob and Grep tools are replaced by embedded bfs and ugrep available through the Bash tool — faster searches without a separate tool round-trip (Windows and npm-installed builds unchanged)

• Windows: cached where.exe executable lookups per process for faster subprocess launches

• Default effort for Pro/Max subscribers on Opus 4.6 and Sonnet 4.6 is now high (was medium)

• Fixed Plain-CLI OAuth sessions dying with "Please run /login" when the access token expires mid-session — the token is now refreshed reactively on 401

• Fixed WebFetch hanging on very large HTML pages by truncating input before HTML-to-markdown conversion

• Fixed a crash when a proxy returns HTTP 204 No Content — now surfaces a clear error instead of a TypeError

• Fixed /login having no effect when launched with CLAUDE_CODE_OAUTH_TOKEN env var and that token expires

• Fixed prompt-input undo (Ctrl+_) doing nothing immediately after typing, and skipping a state on each undo step

• Fixed NO_PROXY not being respected for remote API requests when running under Bun

• Fixed rare spurious escape/return triggers when key names arrive as coalesced text over slow connections

• Fixed SDK reload_plugins reconnecting all user MCP servers serially

• Fixed Bedrock application-inference-profile requests failing with 400 when backed by Opus 4.7 with thinking disabled

• Fixed MCP elicitation/create requests auto-cancelling in print/SDK mode when the server finishes connecting mid-turn

• Fixed subagents running a different model than the main agent incorrectly flagging file reads with a malware warning

• Fixed idle re-render loop when background tasks are present, reducing memory growth on Linux

• [VSCode] Fixed "Manage Plugins" panel breaking when multiple large marketplaces are configured

• Fixed Opus 4.7 sessions showing inflated /context percentages and autocompacting too early — Claude Code was computing against a 200K context window instead of Opus 4.7's native 1M