4Claude Code Release Notes·
Claude Code 2.1.191 release: /rewind support, MCP reliability improvements, 37% CPU reduction
Anthropic shipped Claude Code version 2.1.191 with a notable set of bug fixes and performance improvements. Key additions include /rewind support for resuming conversations before a /clear, roughly 37% CPU reduction during streaming via coalesced text updates, and improved MCP server reliability with retry logic for transient network errors. Several agent-related bugs were fixed, including background agents resurrecting after being stopped and slash commands being incorrectly forwarded to background sessions.
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Claude Code 2.1.203 release: major background agent reliability fixes and MCP roots integration
Anthropic released Claude Code version 2.1.203, a substantial patch addressing over 25 bugs primarily affecting background agent sessions, subagent orchestration, and worktree isolation. Key fixes include automatic recovery when daemon session tokens go stale, correct subagent state carry-over when returning to sessions, and PATH/environment variable inheritance issues on Windows. The release also adds MCP roots/list integration for working directories and improves streaming responsiveness.
Claude Code 2.1.199 release: multi-agent reliability and background agent fixes
Anthropic released Claude Code version 2.1.199, a patch-heavy update addressing roughly 25 bugs across multi-agent orchestration, background agent lifecycle management, SSL/TLS error handling, and streaming response reliability. Key fixes include subagents silently swallowing errors or partial work on rate-limit/server failures, a Linux daemon self-termination bug every ~50 seconds after unclean shutdown, and a macOS SSH cold-start regression from 2.1.196. The release also improves retry behavior for transient 429 errors and raises default retry counts via CLAUDE_CODE_RETRY_WATCHDOG.
Claude Code 2.1.186 adds MCP CLI auth, agent-team improvements, and numerous fixes
Claude Code version 2.1.186 ships new CLI commands for authenticating MCP servers without the interactive menu (`claude mcp login/logout`), including SSH-compatible stdin redirect support. Agent-team behavior is improved: background subagents now surface permission prompts in the main session rather than auto-denying, teammate spawns inherit the leader's effort level, and subagents looping on schema validation failures now abort after 5 attempts. The release also fixes over 20 bugs spanning streaming reliability, subagent transcript handling, Chrome tab-group isolation, and session cost display for Enterprise/Team subscribers.
Claude Code 2.1.196 release: org-default models, MCP security fix, background agent reliability improvements
Anthropic released Claude Code version 2.1.196 with a notable security fix preventing untrusted workspace .mcp.json servers from auto-spawning, and added support for organization-level default model configuration via the admin console. The release includes significant background agent reliability improvements — long-running workflows now survive process restarts on all platforms including Windows — plus a streaming idle watchdog enabled by default that aborts and retries stalled response streams after 5 minutes. Numerous bug fixes address agent session state management, MCP OAuth scope handling, PowerShell compatibility, and a /code-review token usage reduction of ~25%.
Claude Code 2.1.187 release: sandbox credentials, org model restrictions, MCP timeout fixes
Anthropic released Claude Code version 2.1.187 with a mix of security, reliability, and UX improvements. Notable additions include a sandbox.credentials setting to block credential file access in sandboxed commands, org-level model restriction enforcement in the model picker, and mouse click support in fullscreen menus. Key bug fixes address remote MCP tool calls hanging indefinitely (now abort after 5 minutes), subagent depth tracking on resume, leaked agent worktree registrations, and CJK text mojibake in certain terminals.
Claude Code 2.1.181 release: /config syntax, Apple Events sandbox, subagent improvements, and ~40 bug fixes
Anthropic released Claude Code version 2.1.181 with several new features including a /config key=value prompt syntax for setting any configuration option, an opt-in Apple Events sandbox permission on macOS, and a new CLAUDE_CLIENT_PRESENCE_FILE environment variable for suppressing mobile push notifications. The release also includes improvements to subagent panel UX (auto-hide, depth limits, elapsed time fixes), streaming of long paragraphs, and auto-retry on mid-thinking connection drops. Approximately 40 bug fixes address issues ranging from 0-byte file writes on network drives, macOS TUI freezes, startup regressions, and credential refresh loops.
Claude Code 2.1.195 patch: hook matcher fixes, voice dictation improvements, background agent stability
Anthropic released Claude Code version 2.1.195 with a collection of bug fixes and improvements. Key fixes include correcting hook matchers with hyphenated identifiers to use exact matching instead of substring matching, resolving voice dictation failures for space-less languages (Japanese, Chinese, Thai) and macOS device-change silence capture, and fixing background agent data loss and crash recovery issues. The release also adds a new environment variable to disable mouse interactions in fullscreen mode and improves Linux voice mode diagnostics and remote session startup UX.
Claude Code 2.1.176 release: session language, Bedrock caching, model allowlist fixes, Remote Control improvements
Anthropic released Claude Code version 2.1.176 with a mix of new features and bug fixes. Notable additions include session titles generated in the conversation language, a new footerLinksRegexes setting, and improved AWS Bedrock credential caching. Key fixes address model allowlist enforcement (alias models can no longer bypass blocked-model restrictions), auto-mode fallback for organizations without Opus 4.8 enabled, hook path pattern matching, and numerous Remote Control and background-session reliability issues across Linux, Windows, and tmux environments.