Skip to content
Back

AI posts

AI release notes

Anthropic's official release notes. Claude apps: the website, desktop and phone apps. Claude Code: Claude's coding assistant. Claude API: what developers use to build Claude into their own products.

Compiled by the Toolstash team · Updated

  1. Claude Code

    Claude Code 2.1.186

    5 new20 fixes8 other

    Added claude mcp login and claude mcp logout to authenticate MCP servers from the CLI without opening the interactive /mcp menu, with --no-browser stdin redirect support for completing over SSH. Added status filtering (press f) to the /workflows agent detail view.

  2. Claude API

    MCP tunnels: the management API moved from /v1/organizations/tunnels on the Admin API to /v1/tunnels on the…

    The new surface uses the anthropic-beta: mcp-tunnels-2026-06-22 header and the workspace:manage_tunnels WIF scope. The previous surface remains available during a migration window.

  3. Claude Code

    Claude Code 2.1.185

    1 other

    The stream-stall hint now reads "Waiting for API response · will retry in …" instead of "No response from API · Retrying in …", and triggers after 20s of silence instead of 10s.

  4. Claude Code

    Claude Code 2.1.183

    3 new11 fixes3 other

    Added a warning when the requested model is deprecated or automatically updated to a newer model, shown on stderr in print mode (-p) and now also covering models set in agent frontmatter. Added attribution.sessionUrl setting to omit the claude.ai session link from commits and PRs in web and Remote Control sessions.

  5. Claude API

    The Python, TypeScript, Go, Java, Ruby, PHP, and C# SDKs now include support for code_execution_20260120,…

    To adopt it, set the tool’s type to code_execution_20260120; no beta header is required. It’s available on Claude Fable 5, Claude Mythos 5, Claude Opus 4.5 and newer, and Claude Sonnet 4.5 and newer; see the code execution tool’s API support section.

  6. Claude Code

    Claude Code 2.1.181

    3 new29 fixes7 other

    Added /config key=value syntax to set any setting from the prompt (e.g. /config thinking=false) — works in interactive, -p, and Remote Control. Added sandbox.allowAppleEvents opt-in setting that lets sandboxed commands send Apple Events on macOS.

  7. Claude Code

    Claude Code 2.1.179

    8 fixes1 other

    Fixed mid-stream connection drops: partial responses are now preserved instead of showing a raw error, and the spinner no longer gets stuck at "running tool". Fixed mouse-wheel scrolling in WSL2 under Windows Terminal and VS Code (regression in 2.1.172).

  8. Claude Code

    Claude Code 2.1.178

    1 new13 fixes8 other

    Added Tool(param:value) syntax for permission rules to match a tool's input parameters (with * wildcard), e.g. Agent(model:opus) to block Opus subagents.

  9. Claude API

    We’ve retired the Claude Sonnet 4 model and the Claude Opus 4 model

    All requests to these models on the Claude API will now return an error. We recommend upgrading to Claude Sonnet 4.6 and Claude Opus 4.8 respectively. Researchers can request ongoing access through the External Researcher Access Program.

  10. Claude Code

    Claude Code 2.1.177

  11. Claude Code

    Claude Code 2.1.176

    1 new18 fixes3 other

    Added footerLinksRegexes setting for regex-matched link badges in the footer row, configurable via user or managed settings.

  12. Claude Code

    Claude Code 2.1.175

    1 new

    Added enforceAvailableModels managed setting — when enabled, the availableModels allowlist also constrains the Default model (a Default that would resolve to a disallowed model now falls back to the first allowed model), and user or project settings can no longer widen a managed availableModels list.

  13. Claude Code

    Claude Code 2.1.174

    2 new11 fixes

    Added wheelScrollAccelerationEnabled setting to disable mouse-wheel scroll acceleration in fullscreen mode. [VSCode] Added usage attribution to the Account & usage dialog (/usage) showing cache misses, long context, subagents, and per-skill/agent/plugin/MCP breakdowns over the last 24h or 7d.

  14. Claude appsAnnouncement

    Access to Claude Fable 5 and Claude Mythos 5 suspended, plus 1 more change

    We've suspended access to Claude Fable 5 and Claude Mythos 5. We aim to return access as quickly as we can. When Claude writes a draft in chat or Claude Cowork (a report, a plan, a brief), it opens right beside your chat. Highlight the part you want changed, type the change, and Claude makes the edit right where you marked it. No switching apps, no re-describing paragraphs in chat.

  15. Claude Code

    Claude Code 2.1.173

    2 fixes

    Fixed Fable 5 model names with a [1m] suffix not being normalized — Fable 5 includes 1M context by default, so the suffix is now stripped automatically. Fixed a spurious "sandbox dependencies missing" startup warning on Windows when sandbox was enabled in settings.

  16. Claude API

    The code execution tool now supports code_execution_20260521, which discloses the 90-second per-cell…

    No beta header is required. The web search tool and web fetch tool now support web_search_20260318 and web_fetch_20260318, adding a response_inclusion parameter to drop consumed result blocks from the API response for agentic workflows.

  17. Claude Code

    Claude Code 2.1.172

    2 new18 fixes10 other

    Added a search bar when browsing a marketplace's plugins in /plugin. Added model attribute to the claude_code.lines_of_code.count OTEL metric.

  18. Claude API

    The GET /v1/environments/{id}/work endpoint, which lists pending work for a self-hosted sandbox, is now…

  19. Claude Code

    Claude Code 2.1.170

    1 fix1 other

    Introducing Claude Fable 5: a Mythos-class model that we’ve made safe for general use. Fable’s capabilities exceed those of any model we’ve ever made generally available. Update to version 2.1.170 for access. https://www.anthropic.com/news/claude-fable-5-mythos-5. Fixed sessions not saving transcripts (and not appearing in --resume) when launched from the VS Code integrated terminal or any shell that inherited Claude Code environment variables.

  20. Claude API

    Claude Fable 5 and Claude Mythos 5 use the tokenizer introduced with Claude Opus 4.7

    Compared to models before Claude Opus 4.7, the same text produces roughly 30% more tokens. The exact increase depends on the content and workload shape. Use the token counting API with model: "claude-fable-5" to measure your prompts under the new tokenizer. Claude Fable 5 runs safety classifiers on requests and during response generation. The stop_details.category field on refusal responses now includes "reasoning_extraction" on Claude Fable 5, returned when a request is blocked under Anthropic’s Terms of Service restrictions on reverse engineering or duplicating model outputs. On Claude Fable 5 and Claude Mythos 5, adaptive thinking is the only thinking mode: thinking: {"type": "disabled"} is not supported, and manual extended thinking budgets and assistant prefill are not supported (both return a 400 error). On Claude Fable 5 and Claude Mythos 5, thinking.display defaults to "omitted", the same as Claude Opus 4.8, Claude Opus 4.7, and Claude Mythos Preview; set display: "summarized" to receive readable thinking summaries. Claude Fable 5 requires 30-day data retention and is not available under zero data retention. Claude Managed Agents now supports scheduled deployments, letting you run sessions on a cron schedule without managing your own scheduler. Claude Managed Agents vaults now support environment variable credentials, so you can securely inject secrets into the agent’s sandbox for CLIs, SDKs, and other services that authenticate through environment variables. The Compliance API Activity Feed (GET /v1/compliance/activities) is now available on Claude Platform on AWS. The session.thread_* webhook events now include a session_thread_id field identifying the multiagent thread that triggered the event. We’ve released a Swift package in beta that adds Claude as a server-side LanguageModel in Apple’s Foundation Models framework.

  21. Claude appsAnnouncement

    Claude Fable 5 launch

    We launched Claude Fable 5, a Mythos-class model that we’ve made safe for general use.

  22. New modelAnnouncement

    New models: Claude Fable 5 and Claude Mythos 5

    We’ve launched Claude Fable 5 (claude-fable-5), our most capable model open to all customers, alongside Claude Mythos 5 (claude-mythos-5) for Project Glasswing participants. Both models support a 1M token context window by default, 128k max output tokens, and always-on adaptive thinking.

  23. Claude Code

    Claude Code 2.1.169

    4 new14 fixes12 other

    Added --safe-mode flag (and CLAUDE_CODE_SAFE_MODE) to start Claude Code with all customizations (CLAUDE.md, plugins, skills, hooks, MCP servers) disabled for troubleshooting. Added /cd command to move a session to a new working directory without breaking the prompt cache mid-session.

  24. Claude Code

    Claude Code 2.1.168

    1 other

    Bug fixes and reliability improvements.

  25. Claude Code

    Claude Code 2.1.167

    1 other

    Bug fixes and reliability improvements.

  26. Claude Code

    Claude Code 2.1.166

    2 new14 fixes5 other

    Added fallbackModel setting to configure up to three fallback models tried in order when the primary model is overloaded or unavailable; --fallback-model now also applies to interactive sessions. Added glob pattern support in deny rule tool-name position ("*" denies all tools); allow rules reject non-MCP globs, and unknown tool names in deny rules warn at startup.

  27. Claude Code

    Claude Code 2.1.165

    1 other

    Bug fixes and reliability improvements.

  28. Claude API

    We announced the deprecation of the Claude Opus 4.1 model, with retirement on the Claude API scheduled for…

    We recommend migrating to Claude Opus 4.8. Read more in Model deprecations.

  29. Claude Code

    Claude Code 2.1.163

    4 new12 fixes6 other

    Added requiredMinimumVersion and requiredMaximumVersion managed settings — Claude Code refuses to start if its version is outside the allowed range and directs the user to an approved version. Added /plugin list command to list installed plugins, with --enabled/--disabled filters.

  30. Claude Code

    Claude Code 2.1.162

    15 fixes13 other

    claude agents --json now includes waitingFor showing what a waiting session is blocked on (e.g. permission prompt). --tools: explicitly listing Grep/Glob now provides the dedicated search tools on native builds with embedded search (previously these names were silently ignored).