What's new in Claude

Claude Code·May 21, 2026

Claude Code 2.1.147

Pinned background sessions (Ctrl+T in claude agents) now stay alive when idle, are restarted in place to apply Claude Code updates, and are shed under memory pressure only after non-pinned sessions. Renamed /simplify to /code-review. It now reports correctness bugs at a chosen effort level (e.g., /code-review high); pass --comment to post findings as inline GitHub PR comments. The old cleanup-and-fix behavior has been removed.

Claude Code·May 21, 2026

Claude Code 2.1.146

Renamed /simplify to /code-review with an optional effort level (e.g. /code-review high). Auto mode no longer suppresses AskUserQuestion when the user or a skill explicitly relies on it.

Claude apps·May 21, 2026

Claude now works with more security and compliance tools

We introduced Claude Compliance API integrations with notable security and compliance tools. Now IT and security teams can govern Claude across our platform and suite of products, the same way they govern other applications in their stack. Learn how to get started with Claude Compliance API integrations.

Claude Code·May 19, 2026

Claude Code 2.1.145

Added claude agents --json to list live Claude sessions as JSON for scripting (tmux-resurrect, status bars, session pickers). Added agent_id and parent_agent_id attributes to claude_code.tool OTEL spans, and fixed trace parenting so background subagent spans nest under the dispatching Agent tool span.

Claude Code·May 19, 2026

Claude Code 2.1.144

Added /resume support for background sessions — sessions started via claude --bg or agent view now appear alongside interactive ones, marked with bg. Added elapsed duration to background subagent completion notifications (e.g. "Agent completed · 3h 2m 5s").

Claude API·May 19, 2026

MCP tunnels is now available as a research preview, so you can connect to MCP servers in your private network

Self-hosted sandboxes are now available for Claude Managed Agents, as an alternative to running tool execution in Anthropic's infrastructure. With Claude Managed Agents, you can now update the agent's MCP server and tool configurations associated with an active session. With Claude Managed Agents, large outputs from agent_toolset and MCP tools exceeding 100K characters (about 25K tokens) are now automatically spilled to a file in the sandbox.

Claude API·May 18, 2026

The web search tool now returns richer SEC filing data, making it easier to ground financial research…

Claude Code·May 15, 2026

Claude Code 2.1.143

Added plugin dependency enforcement: claude plugin disable now refuses when another enabled plugin depends on the target (with a copy-pasteable disable-chain hint), and claude plugin enable force-enables transitive dependencies. Added projected context cost (per-turn and per-invocation token estimates) to the /plugin marketplace browse pane.

Claude Code·May 14, 2026

Claude Code 2.1.142

Added new claude agents flags: --add-dir, --settings, --mcp-config, --plugin-dir, --permission-mode, --model, --effort, and --dangerously-skip-permissions to configure dispatched background sessions.

Claude Code·May 13, 2026

Claude Code 2.1.141

Added terminalSequence field to hook JSON output so hooks can emit desktop notifications, window titles, and bells without a controlling terminal. Added CLAUDE_CODE_PLUGIN_PREFER_HTTPS to clone GitHub plugin sources over HTTPS instead of SSH, for environments without a GitHub SSH key.

Claude API·May 13, 2026

We've launched cache diagnostics in public beta

Pass diagnostics.previous_message_id on a Messages request and the API reports a cache_miss_reason explaining where the prompt cache prefix diverged from the previous turn. Include the cache-diagnosis-2026-04-07 beta header in your requests.

Claude Code·May 12, 2026

Claude Code 2.1.140

Improved Agent tool subagent_type matching to accept case- and separator-insensitive values (e.g. "Code Reviewer" resolves to code-reviewer). Updated agent color palette.

Claude API·May 12, 2026

Fast mode now supports Claude Opus 4.7

Set speed: "fast" with model: "claude-opus-4-7" and the fast-mode-2026-02-01 beta header for significantly faster output token generation at premium pricing. Pricing, rate limits, and access are the same as for Opus 4.6 fast mode; interested customers should join the waitlist.

Claude Code·May 11, 2026

Claude Code 2.1.139

Added agent view (Research Preview): a single list of every Claude Code session — running, blocked on you, or done. Run claude agents to get started. See https://code.claude.com/docs/en/agent-view. Added /goal command: set a completion condition and Claude keeps working across turns until it's met. Works in interactive, -p, and Remote Control. Shows live elapsed/turns/tokens as an overlay panel.

New model·May 11, 2026

New model: Claude Platform on AWS

We've launched Claude Platform on AWS, bringing the Claude API to Anthropic-managed infrastructure accessible through AWS, with AWS billing and IAM authentication. Access the full Messages API, Files API, Message Batches API, Claude Managed Agents, Agent Skills, code execution, and tool use through native AWS endpoints. Learn more in Claude Platform on AWS.

Claude Code·May 9, 2026

Claude Code 2.1.138

Internal fixes.

Claude Code·May 9, 2026

Claude Code 2.1.137

[VSCode] Fixed extension failing to activate on Windows.

Claude Code·May 8, 2026

Claude Code 2.1.136

Added CLAUDE_CODE_ENABLE_FEEDBACK_SURVEY_FOR_OTEL to re-enable the session quality survey for enterprises capturing responses through OpenTelemetry. Added settings.autoMode.hard_deny for auto mode classifier rules that block unconditionally regardless of user intent or allow exceptions.

Claude Code·May 7, 2026

Claude Code 2.1.133

Added worktree.baseRef setting (fresh | head) to choose whether --worktree, EnterWorktree, and agent-isolation worktrees branch from origin/ or local HEAD. Note: the default fresh changes EnterWorktree's base back to origin/ (it has been local HEAD since 2.1.128) — set worktree.baseRef: "head" to keep unpushed commits in new worktrees. Added sandbox.bwrapPath and sandbox.socatPath managed settings (Linux/WSL) to specify custom bubblewrap and socat binary locations.

Claude Code·May 6, 2026

Claude Code 2.1.132

Added CLAUDE_CODE_SESSION_ID environment variable to the Bash tool subprocess environment, matching the session_id passed to hooks. Added CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN=1 env var to opt out of the fullscreen alternate-screen renderer and keep the conversation in the terminal's native scrollback.

Claude Code·May 6, 2026

Claude Code 2.1.131

Fixed VS Code extension failing to activate on Windows due to a hardcoded build path in the bundled SDK (createRequire polyfill bug). Fixed Mantle endpoint authentication failing with missing x-api-key header.

Claude Code·May 6, 2026

Claude Code 2.1.129

Added --plugin-url flag to fetch a plugin .zip archive from a URL for the current session. Added CLAUDE_CODE_FORCE_SYNC_OUTPUT=1 env var to force-enable synchronized output on terminals that auto-detection misses (e.g. Emacs eat).

Claude API·May 6, 2026

Multiagent orchestration and Outcomes are now in public beta under the standard managed-agents-2026-04-01…

Claude Managed Agents vault credential background refresh is now supported for mcp_oauth credentials. Webhooks for Claude Managed Agents are now supported. Additional filtering and sorting options are now supported for Claude Managed Agents. Dreams for Claude Managed Agents are now available as a research preview.

Claude Code·May 4, 2026

Claude Code 2.1.128

Bare /color (no args) now picks a random session color. /mcp now shows the tool count for connected servers and flags servers that connected with 0 tools.

Claude API·May 4, 2026

We've launched Workload Identity Federation

Authenticate workloads to the Claude API with short-lived OIDC tokens from your own identity provider (AWS IAM, Google Cloud, GitHub Actions, Kubernetes, Microsoft Entra ID, Okta, SPIFFE, and more) instead of long-lived static API keys. Configure issuers and federation rules in the Claude Console, and the SDK handles token exchange and refresh automatically.

Claude Code·May 1, 2026

Claude Code 2.1.126

The /model picker now lists models from your gateway's /v1/models endpoint when ANTHROPIC_BASE_URL points at an Anthropic-compatible gateway. - Added claude project purge [path] to delete all Claude Code state for a project (transcripts, tasks, file history, config entry) — supports --dry-run, -y/--yes, -i/--interactive, and --all.

Claude API·Apr 30, 2026

We've retired the 1M token context window beta for Claude Sonnet 4.5 and Claude Sonnet 4

The beta header now has no effect on these models, and requests exceeding the standard 200k-token context window return an error. To use the 1M context window, migrate to Claude Sonnet 4.6 or Claude Opus 4.6, where it's included at standard pricing with no beta header required.

Claude Code·Apr 29, 2026

Claude Code 2.1.123

Fixed OAuth authentication failing with a 401 retry loop when CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS=1 is set.

Claude API·Apr 29, 2026

We've released the Claude API skill, an open-source Agent Skill that gives Claude up-to-date reference…

The skill is bundled with Claude Code and available in the Anthropic skills repository.