Claude Code News
Claude Code 2.1.300
October 14, 2026
Added virtualText to a mod's prompt decorations: text drawn in the prompt box that never enters the draft or the submitted prompt Added cache_creation_5m_tokens and cache_creation_1h_tokens to the OpenTelemetry api_request event, splitting cache writes by lifetime Added $.ui.view({ agentId }) for mods: shows an agent's transcript in the main view when you ask, and $.ui.view({}) goes back Added a dir prop on a mod's Text for right-to-left text: on Windows and in VS Code's terminal its rows read in that direction and sit flush right Added /advisor on Claude Platform on AWS; no advisor runs until you pick one with /advisor, advisorModel or --advisor, and CLAUDE_CODE_DISABLE_ADVISOR_TOOL=1 turns it off Added OpenTelemetry GenAI semantic-convention attributes to trace spans, such as gen_ai.provider.name, gen_ai.conversation.id, gen_ai.tool.name and error.type Added support for rewriting a workflow agent's prompt and model in the agent.spawn mod hook, which could only refuse workflow agents before Added the prompt.change mod hook, raised when the prompt box's text changes without a typed edit: a recalled history entry, a clear, an undo, or a plugin's fill Fixed cloud sessions telling Cla
Claude Code 2.1.299
October 14, 2026
Added CLAUDE_CODE_DISABLE_FILE_MENTIONS environment variable: Claude gets the paths of @ file mentions to read with its file tools, not the files' contents Added idle compaction in the terminal: a 200K+ token conversation left idle for about 54 minutes is compacted before its one-hour prompt cache expires, so your next message doesn't reprocess it all Added CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS to change idle compaction's 200K-token minimum; "idleCompaction": false in settings.json turns it off. Both need v2.1.290 or later Added $.prompt.media so a prompt.submit hook of a mod installed by managed settings can read the bytes of an image or document attached to the prompt Added $.session.identity() for mods installed by managed settings: how the session is signed in, and its organization and email when managed forceLoginOrgUUID lists that organization Added size, weight, mono and tabular to a mod's Text and named spacing steps (xs to xl) to its Box; bold is deprecated in favor of weight Added --shutdown-drain-sec to claude self-hosted-runner orchestrator: on SIGTERM it stops polling and gives the poll in flight and running spawn hooks up to that many seconds to finish Added the skill's
Claude Code 2.1.296
October 9, 2026
Added a code key to the Claude apps gateway's managed.policies[]: the same settings as cli, also applied in Claude Desktop's Code tab; beside desktop, it turns on Claude Desktop's gateway mode Added autoCompactWindow to subagent frontmatter and --agents definitions, so a subagent can auto-compact earlier than the main conversation's window Added CLAUDE_CODE_WORKFLOW_SUBAGENT_MODEL to run every workflow agent on one model while other subagents keep theirs Added CLAUDE_CODE_OVERLOADED_RETRY_MAX_DELAY_MS environment variable to set a longer maximum delay for the backoff when retrying an overloaded (529) request Added a note in /plugin on a plugin whose hooks are left out because another enabled plugin has the same name Added an allow_large option to the Read tool so Claude can read a text file past the usual size limits in one call when it needs the whole file and the context has room Fixed managed-settings PreToolUse hooks that deny a tool call with "continue": false, and managed prompt hooks that block one, refusing the call but not ending the turn Fixed PostToolUse hooks in managed settings not applying updatedMCPToolOutput in some sessions Fixed headless sessions starting a folder
Claude Code 2.1.295
October 8, 2026
Added onFailure: "block" for command and HTTP hooks: a hook that can't start, times out, or exits with an unexpected code blocks the action instead of letting it through Added Program Status Protocol (OSC 7501) support: terminals that implement it can show whether Claude Code is working, waiting on you, or done Added quoted text to the /copy picker, so a drafted message copies without its > markers Added a warning to claude plugin install, enable, disable and marketplace add when the settings file they write to does not load Added a line on stderr, when it is a terminal, that says what a claude -p run is waiting for when it stays open after its last turn Added support for timeouts.upstream_ttfb_ms on the Claude apps gateway's Bedrock, Vertex, Foundry and other cloud upstreams: a value you set now limits how long a stream may take to start there, after which it fails over or gets a 502 Added a "Backgrounding cancelled" message when you stop the turn while ← is waiting for the current tool to finish Added an optional models list to every Claude apps gateway upstream: only the listed models are sent there, on failover too, and one * in an entry is a wildcard Added support for forceLog
Claude Code 2.1.294
October 8, 2026
Fixed prompt and agent hooks written as instructions (such as "Block commands that...") allowing what they should block Improved how prompt hooks on Stop and SubagentStop written as instructions (such as "Carry on if the build is broken") are judged, so Claude is less likely to stop early
Claude Code 2.1.293
October 7, 2026
Added Claude Haiku 5.5 (claude-haiku-5-5), now the default Haiku model on the Anthropic API — 1M context, $0.10/$0.50 per Mtok ($0.50/$2.50 for prompts over 100K) Added agentType to the subagentStatusLine payload, so scripts can tell custom subagent types apart Added isDeferred to $.tool.register for mods: false lists the tool's schema in the prompt from the start instead of behind tool search Fixed Claude sometimes treating its own last actions before a context compaction as done after it, and retracting or redoing finished work Fixed a memory leak where an HTTP MCP connection kept every request it had sent until it closed Fixed a message sent while Claude was working being lost when ← moved the session to the background; if a queued message can't move, ← now stays put and says so Fixed /model effort ←/→ wrapping past the highest or lowest level, which could accidentally save Low as a model's default effort Fixed /tui disconnecting Claude in Chrome in a session started with --chrome, and ignoring --no-chrome Fixed Claude being told to continue or message subagents with SendMessage in sessions, including resumed ones, where a host, a permission rule or a --tools list removed that t
Claude Code 2.1.292
October 6, 2026
Added --marketplace to claude plugin install: adds the marketplace if needed, under the same policy checks as claude plugin marketplace add, then installs the plugin from it Added an effort parameter to the Agent tool, so Claude runs a sub-agent at the effort level you ask for Added CLAUDE_CODE_OVERLOADED_RETRY_BASE_DELAY_MS environment variable to set a longer base delay for the backoff when retrying an overloaded (529) request Added prompt.autocomplete, an event a mod hooks to add its own rows to the prompt box's autocomplete list Added prompt caching to $.model.complete for mods: prompt and system take blocks of text, and cache: true on a block caches the request up to it Added workflow agents to the agent.spawn mod hook, with their run and index, so a mod can refuse them Fixed subagent definitions with permissionMode: auto entering auto mode when auto mode is unavailable (disabled by settings, circuit breaker, or a model that doesn't support it) Fixed sandboxed commands being able to read the staged file copies of /ultrareview uploads under ~/.claude/seed-admin Fixed a managed sandbox read-deny path (and user ones beside it) that appears or re-points mid-session not dropping pr
Claude Code 2.1.291
October 6, 2026
Fixed a regression in 2.1.290 where cloud sessions could drop answers to permission prompts Fixed a regression in 2.1.288 where the last messages of a session could be lost when quitting
Claude Code 2.1.290
October 5, 2026
Added serverToolUses to the result of a mod's turn.step hook: the tool calls the API ran itself (the advisor), each with its id, name, input, start and end Added agentId to the tool.check event of plugin hooks, so a hook can tell a subagent's permission check from the main session's Added ceiling to the question and verdict a mod's tool.check hook reads, naming the approval an organization requires for a tool Added ThemeKey and Color types to the plugin hooks typings, so an editor lists the theme colors a mod's drawing can name Added to claude plugin validate: each hook a mod registers at a gating site is listed with whether it has a .catch (gatingHooks under --json) Added a Deny button to the Claude apps gateway's sign-in approval page: it ends the pending sign-in, so the waiting terminal stops within seconds Added claude attach and claude logs : part of a session name works in place of the id Added /claude-api managed-agents-onboard to set up the Managed Agents pattern a page describes as ant apply files Added /claude-api managed-agents-onboard to build a Console quickstart template, such as deep-researcher, with the ant CLI Added a warning when a managed settings file is a link
Claude Code 2.1.289
October 3, 2026
Fixed a deny or ask rule on a nested part of a compound shell command not holding over a user-installed mod's approval on managed machines Fixed the terminal freezing on short code blocks with many unclosed tags or deeply nested ${ substitutions Fixed Read deny rules not applying to files @-mentioned, changed, or selected in the IDE through a symlink [VSCode] Reverted a 2.1.288 change to claude auth status that may have made sign-outs more frequent Improved how quickly large files open in a plugin code pane by laying the highlighted view out once at its final width Fixed plugin list, plugin eval and plugin update showing a stale copy of a plugin installed from a local folder marketplace, and hot reload for a symlinked --plugin-dir Fixed installed mods not loading in the first session after an upgrade Fixed a plugin's rows above the prompt showing a stale row while the Background tasks dialog was open in fullscreen Fixed plugin panes drawing nothing when a link used a localhost address, an @ in its path, an uppercase host or a file: path Fixed a user-installed plugin being able to rewrite the descriptions of an organization-managed MCP server's sign-in tools Fixed a freeze or forced
Claude Code 2.1.288
October 2, 2026
Added $.ui.selection() for mods: returns the text you last selected in fullscreen mode and, when the selection lies within one transcript row, that row Added a built-in gh api to cloud sessions whose image has no GitHub CLI, and fixed the built-in sending control characters from file names, jq filters or GitHub errors to the terminal Added recovery for a prompt cleared with Ctrl+C: pressing Up on the empty prompt brings the draft back, including pasted text and images Added a re-authenticate prompt when an MCP server asks for more OAuth scope during a tool call Added --max-findings |all to /code-review to report more or fewer findings than the usual limit; the choice is reused until you pass --max-findings default Added Ctrl+F to find a session by name and Alt+↑/↓ to jump between groups in the agents view; both, and rename, can be rebound in keybindings.json Added a screen reader mode announcement of the new permission mode when you approve a plan, including with Shift+Tab Fixed mid-response API timeouts failing the turn: non-interactive sessions and subagents now continue from the partial response, and thinking-only responses are retried Fixed long conversations failing with "Prom
Claude Code 2.1.287
October 1, 2026
Added Claude Mods: plugins may now modify deeper behavior Added You should know, a built-in mod where a side agent watches your back and flags things you or Claude might miss. Turn it on with /plugin enable cc-plugin-you-should-know@builtin (for first-party sessions with telemetry on) Added an n: filter to the agents view that matches session names and tasks; a filter now shows matches in collapsed sections and Enter opens the first match Added prompt_text to the OpenTelemetry user_prompt event, a copy of prompt for backends that nest dotted keys; drop or mask it wherever you drop or mask prompt (anthropics/claude-code#70763) Added URL prompts from MCP servers on the 2025-11-25 protocol, for example to sign in. If a server no longer connects after this update, add "bareElicitationCapability": true to its MCP config entry Windows: Added a startup warning when denying the Bash tool also turns off the PowerShell tool, so Claude has no shell tool Self-hosted runner: Added a built-in gh api (REST only) for sessions that use Anthropic-managed git on macOS and Linux machines where the GitHub CLI is not installed Fixed fast mode staying off in remote sessions owned by an agent with no user
Claude Code 2.1.286
September 30, 2026
Added a count such as "2 of 5" to the permission prompt when several permission requests stack up Added mouse support for the "N more" rows of lists in fullscreen mode: click one to jump to that end of the list, with hover and pressed states Fixed several Claude Code processes and IDE extensions each opening a login browser when gcpAuthRefresh or awsAuthRefresh credentials expire Fixed claude --resume and --continue sometimes losing every turn after a batch of parallel tool calls when the earlier session crashed or was killed Fixed API 400 errors after a tool or hook returned an object, number or boolean instead of text, including in resumed sessions Fixed cloud sessions with very large histories never waking up because the container was stopped while the transcript was still loading Fixed the Claude apps gateway's spend meter pricing 1-hour prompt cache writes at the cheaper 5-minute rate, and counting only the first model call's input tokens on streamed turns that run a server-side tool such as web search Fixed macOS sessions still showing "Not logged in" or "Login expired" after /login succeeds in another Claude Code window when a leftover ~/.claude/.credentials.json exists Fixe
Claude Code 2.1.285
September 29, 2026
Added CLAUDE_CODE_DISABLE_WEB_FETCH environment variable to turn off the WebFetch tool Added claude --desktop to open the Claude desktop app on the current directory, or on a session with --continue / --resume Added claude plugin configure to show a plugin's options and which are unset, or save new values read from stdin with --values-stdin Added .= to claude plugin install --config, so a bundled .mcpb MCP server's own settings can be set at install time and it starts without visiting /plugin → Configure Added allowedProviders managed setting to limit which API providers a machine may use (Anthropic API, a custom endpoint, Bedrock, Mantle, Vertex AI, Foundry, Claude Platform on AWS, or a Cloud gateway) Added CLAUDE_CODE_NONSTREAMING_TIMEOUT_RETRIES environment variable to cap re-sends of a non-streaming fallback request that timed out Fixed claude -p with CLAUDE_CODE_FORK_SUBAGENT=1: a subagent's own Agent call now runs in the foreground, so the subagent gets the child's result Fixed plugin and marketplace installs and updates over SSH ignoring the ssh program set in GIT_SSH or in your git config's core.sshCommand Fixed Claude Code refusing to start when the OS denies reading the m
Claude Code 2.1.284
September 28, 2026
Added Claude Sonnet 5.5 (claude-sonnet-5-5), now the default Sonnet model on the Anthropic API — 1M context, $2/news: [0 per Mtok with $0.20/Mtok cache reads Added a "Yes, but ask again next time" answer to auto mode's prompt before a read outside the working directories, so you can allow that one read and still be asked about later ones Added dollar amounts to the Claude apps gateway spend limit in /usage and the status line (for example "$271.40 / $500.00 spent this month") when the gateway runs this version or later; the status line's rate_limits.spend_limit also gains used_usd, limit_usd and period Added effortSlider:decreaseEffort, increaseEffort and toggleUltracode keybinding actions, so the /effort slider's arrow and Tab keys can be rebound in keybindings.json Added /rate-limit-options to /help and the command menu for claude.ai subscribers, so the usage-limit notices that mention it point to a command you can find Added /mcp reconnect all in the interactive terminal to retry every MCP server that failed to connect or needs authentication at once Added Claude apps gateway startup warnings when a managed policy's availableModels is empty, or leaves out the model Claude Code starts
Claude Code 2.1.283
September 25, 2026
Added x-claude-code-prompt-id to the gateway hint headers so LLM gateways can group the requests that serve one user prompt; opt in with CLAUDE_CODE_GATEWAY_HINT_HEADERS=1 Added availableModelsMatch managed setting: with "exact", an availableModels entry allows only the model version it names, so new releases stay blocked until listed Added deniedModels managed setting to block specific models, even when availableModels allows them Added MCP tool, WebFetch and WebSearch outputs to the tool.output OpenTelemetry span event when OTEL_LOG_TOOL_CONTENT=1 Added /doctor prompt-audit (also /checkup prompt-audit) to audit your CLAUDE.md files, skills, agents and commands for prompting patterns written for older models Added click-to-expand for truncated messages from your other sessions in fullscreen mode Added path to --plugin-dir load-failure entries in the stream-json system/init plugin_errors, naming the directory that did not load Added an opt-in load_test_mode block to the Claude apps gateway config: requests are built and signed but not sent upstream, and clients get a canned reply, so a deployment can be load tested Added a mantle upstream provider to the Claude apps gateway for Ama
Claude Code 2.1.282
September 24, 2026
Added a maxProseWidth setting that caps the width of Claude's prose in wide terminals while tables and code blocks keep the full width Added a startup notice, and /status and claude doctor entries, listing telemetry variables in a project's settings files that were ignored or that turned telemetry off Added the allowClaudeInChromeWithManagedMcp managed setting to let claude --chrome run alongside an exclusive managed-mcp.json; the error shown when Chrome is blocked now names it Added store.readiness_grace_seconds to the Claude apps gateway so /readyz can stay ready through a short Postgres outage such as a database failover Added a scrollbar to the /feedback drafts list in fullscreen mode; it appears while the mouse is over the list Fixed every request failing with a 400 error in conversations whose history holds web search results the API cannot decrypt (for example, from a turn answered through a third-party gateway) Fixed more cases of continued or resumed sessions (--continue, --resume) re-sending earlier messages in a changed form, which could make the API drop Claude's earlier reasoning Fixed earlier extended thinking being dropped when /model, /rename, /artifacts or another
Claude Code Cloud Sessions Leave Research Preview
September 23, 2026
Claude Code cloud sessions are now generally available and keep working on Anthropic-hosted infrastructure after your laptop closes. Start one at claude.ai/code, in the Claude mobile or desktop app, or with claude --cloud in the CLI. Existing subscribers receive one automatic cloud-only trial credit per account: $100 on Pro or $250 on Max. The credit is separate from regular usage limits.
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Claude Code 2.1.281
September 23, 2026
Added Claude apps gateway support for newer Claude Desktop keys in desktop policy blocks, including blockReadsOutsideWorkingDirectories and disableBypassPermissionsMode Added assume_role on Claude apps gateway Bedrock upstreams: the gateway calls Bedrock as an IAM role it assumes through STS, in another AWS account if needed, optionally one session per developer Added guardrail: {id, version} on Claude apps gateway Bedrock upstreams to apply an Amazon Bedrock guardrail to every request sent through them (set it on all Bedrock upstreams or none) Added telemetry.resource_attributes to the Claude apps gateway config, to put fixed labels on the telemetry of Claude Desktop and /login sessions Added "attribution": false in settings.json to hide all commit and PR attribution; older CLI versions skip a settings file that holds it, so keep the object form in files shared across versions Added MCP URL-mode elicitation on 2026-07-28 protocol connections, so servers can ask Claude Code to open a browser-based flow; no waiting dialog is left on screen when the server has no way to confirm completion Added MCP server checks to claude plugin validate: it reports .mcp.json entries that would be si
Claude Code 2.1.280
September 22, 2026
Added Claude Opus 5.5 (claude-opus-5-5), now the default Opus model — 1M context, $4/$20 per Mtok with $0.20/Mtok cache reads Added mouse support to more lists in fullscreen mode: the wheel scrolls the /skills list, and a skill's state options in /plugin can be clicked Added CLAUDE_CODE_MAX_MCP_DESCRIPTION_LENGTH to change the 2,048-character cap on MCP tool descriptions and server instructions for every MCP server in the session Added hook output sizes and the number of oversized outputs saved to a file to the hook_execution_complete OpenTelemetry event Fixed writes through a symlinked path being judged by their in-tree spelling: the prompt names where the write lands, and acceptEdits, allow rules and auto mode no longer approve one landing outside Fixed auto mode retrying an action over and over when a safety check declined to review it; the action is now denied once, noting that retrying won't help Fixed auto mode denying actions over and over without pause when a safety check gave no answer; retries now back off, and the turn stops with a message after ten in a row Fixed Write calls failing validation when a model sends path, file_text, file_content or a stray description inste
Claude Code 2.1.278
September 19, 2026
Changed auto mode for Claude API and Enterprise users, and on Bedrock, Vertex, Foundry and gateways, to default to the server-side classifier, which does not charge for classifier overhead (CLAUDE_CODE_AUTO_MODE_SERVER=0 opts out on Bedrock, Vertex, Foundry and gateways); warns on billed fallback. See https://code.claude.com/docs/en/auto-mode-classifier-billing Added an Auto mode server row to /status showing whether this session's auto mode classifier runs on the server
Claude Code 2.1.277
September 18, 2026
Added AGENTS.md support: in a project with no CLAUDE.md, Claude Code reads AGENTS.md instead; change it under "Project instructions" in /config (not yet on Bedrock, Vertex or Foundry) Added CLAUDE_GATEWAY_PROXY_IS_EGRESS_BOUNDARY=1 for Claude apps gateways whose only egress is a forward proxy: every outbound request hands the proxy the hostname instead of resolving it locally Added an optional headers: map on Claude apps gateway upstreams, to send static headers to a proxy you run in front of a provider Added a line saying a background task's update is waiting when it finishes while a panel such as /tasks is open Fixed claude -p and Agent SDK sessions that could hang with no result after an internal error; they now report the error and exit with code 1 Fixed conversations failing every request with "text content blocks must be non-empty" when an earlier assistant turn held an empty text block beside other content, including after --resume Fixed being unexpectedly logged out when an older Claude Code build (for example an IDE extension's bundled CLI) runs on the same machine as the current one Fixed interactive start-up hanging or showing an error for ANTHROPIC_API_KEY users when ~/
Claude Code 2.1.276
September 18, 2026
Fixed every request failing with 400 … Input tag 'advisor_20260301' when ANTHROPIC_BASE_URL points at a proxy or gateway (2.1.275 regression)
Projects in Claude Code Enter Beta
September 17, 2026
Claude Code is rolling out Projects on desktop and web. Start with one conversation and Claude splits work into threads, runs them as parallel cloud sessions, shares context between them, and keeps going when your computer is offline. The initial beta is for select Pro and Max users who already use cloud sessions and have not used Claude Projects before; existing Projects users will be included later. Local workflow support is planned, and users can join the waitlist for earlier access.
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Claude Code 2.1.275
September 17, 2026
Added the signed-in account to Claude apps gateway sign-in: when the gateway names it, you confirm it before the credential is saved, and /status shows it Added a send-now key (ctrl+enter, or ctrl+x ctrl+s) that interrupts the current turn and sends all queued messages at once; sent and queued messages show in gray until the model receives them Added a startup warning when a configured otelHeadersHelper fails, so sessions that silently export no telemetry are noticed Added syncing of the skills and plugins enabled on your claude.ai account to terminal sessions signed in with it; opt out with syncClaudeAiSkills: false or syncClaudeAiPlugins: false Added /plugin install --marketplace , which offers to add the marketplace before installing the plugin Fixed a restored memory file's age note changing between requests after a compaction or resume, which caused prompt cache misses Fixed --forward-subagent-text stream-json and SDK output dropping the messages of subagents spawned by a context: fork skill, and of forked skills invoked by a subagent or another forked skill Fixed @-mention file suggestions being buried below MCP resources when using a custom fileSuggestion command or typing @
Claude Code 2.1.274
September 16, 2026
Added a visible warning when memory usage is critical, with steps to free memory or restart safely Added CLAUDE_CODE_MCP_STARTUP_WAIT_MS to bound how long the first non-interactive turn waits for connecting MCP servers (0 = don't wait) Added effort attribute to the claude_code.llm_request OpenTelemetry trace span, matching the api_request event Added claude_code.managed_settings_resolved OTel event: managed-settings sources and policy helper state; redacted settings and digests with OTEL_LOG_MANAGED_SETTINGS=1 Added store.connect_timeout_seconds to the Claude apps gateway config to lengthen the Postgres connect timeout (default 5 seconds), and improved the boot error when the database is unreachable to point to store.postgres_url and the configured timeout Added enduser.sub, the IdP subject, to the telemetry Claude Desktop and Cowork send through a Claude apps gateway Added a Claude apps gateway warning when a replica has more requests open than the 256 it sends upstream at once, and a startup log line showing that limit Added click-to-expand for collapsed teammate and agent messages in fullscreen mode Fixed sessions getting stuck endlessly retrying "unexpected tool_use_id" 400 err
Claude Code 2.1.273
September 15, 2026
Added x-claude-code-request-class, x-claude-code-agent-type, x-claude-code-prev-tool-durations, x-claude-code-compaction and x-claude-code-context-compacted request headers for LLM gateways; opt in with CLAUDE_CODE_GATEWAY_HINT_HEADERS=1 Added a notification when an MCP server disconnects mid-session and automatic reconnection gives up, pointing at /mcp Added forking a session started with claude --remote-control or /remote-control from the Claude app; the fork runs as a background session on your computer Fixed Bash commands the permission checker cannot fully analyze skipping the prompt under permissions.blockReadsOutsideWorkingDirectories, and a subshell hiding a dangerous rm in bypass mode Fixed skills synced from claude.ai staying available after your organization turns Skills off; they now move to the recoverable trash Fixed allowManagedMcpServersOnly, deniedMcpServers and disableClaudeAiConnectors set via MDM or managed-settings.json being ignored when server-managed settings are also present Fixed 401/403 errors on Bedrock, Vertex and Foundry, and Claude apps gateway 403s, telling you to run /login; the message now names the credential to refresh or points to your gateway a
Claude Code 2.1.271
September 14, 2026
Added fast mode in Claude Code Remote sessions (cloud and self-hosted runners): the host's fast-mode setting or /fast typed in the session applies where your organization allows it Added mouse support to the /config panel in fullscreen mode: the wheel scrolls the settings list, a click on a setting's value changes it, and the row under the pointer is highlighted Added claude self-hosted-runner --drain-marker-file : when that file exists at a SIGTERM drain, the runner reports its exit to the server as a host drain (telemetry only) Added per-command allowed_domains to Bash, PowerShell and Monitor in auto mode with sandboxing: the hosts a command needs are reviewed with it and opened for it alone; other hosts are refused Added omitClaudeMd to agent frontmatter and --agents JSON, letting custom and plugin subagents run without user, project and local CLAUDE.md files; managed policy files still load Added --accept-command to claude plugin install and claude plugin update to accept exactly the command a previous --json run displayed, instead of -y Added support for a multiplier above 1, up to 10, in the modelPricing managed setting and the Claude apps gateway pricing block, for marked-up
Claude Code 2.1.270
September 12, 2026
Fixed read-only git commands in Bash unexpectedly asking for permission after a session had been running for a while (regression in 2.1.269)
Claude Code Plugin Eval
September 11, 2026
Claude Code now includes plugin eval: create test cases, run a plugin or skill against them, score the results, and compare those runs with and without the plugin to see the value it adds.
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Claude Code 2.1.269
September 11, 2026
Added claude plugin eval: run a plugin's eval suite against Claude Code and get scored, reproducible results (JSON + HTML report); see claude plugin eval --help Added /output-style [name] to list and switch output styles, including over Remote Control and in cloud and other headless sessions Added a diff of the files a Bash command changed to the Bash tool result when the Bash tool handles file edits (setting bashEditDiffEnabled) Added OTEL_METRICS_INCLUDE_REPOSITORY to tag OpenTelemetry metrics and events with vcs.* repository attributes; commit events get vcs.ref.head.* with OTEL_LOG_TOOL_DETAILS Added CLAUDE_CODE_GATEWAY_MODEL_DISCOVERY_TIMEOUT_MS to extend the LLM gateway /v1/models discovery timeout (default 3s) Added a spinner tip suggesting /focus for a view with just your prompt, a one-line work summary, and the response Added CLAUDE_CODE_WORKFLOW_MAX_CONCURRENT_AGENTS (1–256) to raise the Workflow tool's per-run concurrent agent limit for inference-bound fan-outs Fixed the prompt cache being partially invalidated on the turn after a response was cut off at the output-token limit and automatically resumed Fixed a case where resuming a session after interrupting Claude mid-t
Claude Code 2.1.268
September 10, 2026
Added to the Claude apps gateway: with pricing: set in gateway.yaml, signed-in Claude Code clients receive the same rates through managed settings, so /cost and telemetry match the spend meter Added a startup warning for gateways when access_control.allow_cidrs is empty, and a one-time warning the first time a request arrives from a public address Added the gatewayInternalNetworks managed setting, letting administrators allow /login to a Claude apps gateway on their organization's own public IPv4 block Added claude self-hosted-runner --remove-session-state (default off): delete each session's per-session directories under /_sessions/ when the session ends Added configDirectory to the output of claude auth status --json Added --json to claude plugin install, uninstall, update, enable and disable, and errorDetails/noteDetails to each row of claude plugin list --json Added browser-tab icons for published artifacts, chosen by Claude to match each page Fixed every turn failing with HTTP 400 on third-party Anthropic-compatible endpoints (ANTHROPIC_BASE_URL) since 2.1.265: a regex in the Artifact tool's input schema that those endpoints reject Fixed WebFetch hanging indefinitely on a serv
Claude Code 2.1.267
September 9, 2026
Added maxEffortLevel setting (top-level or per model under modelSettings): caps the effort level on every provider, including Bedrock, Vertex and Foundry; users can still pick a lower level Added --system-prompt-snapshot off to render the system prompt fresh on every request instead of reusing the conversation's recorded prompt (for iterating on prompt text) Fixed Cowork scheduled tasks in the cloud failing at startup for organizations whose managed settings require sandboxing Fixed /context and other local command output rendering blank on mobile clients Fixed shift+enter and option+backspace not working after reconnecting to a tmux or ssh session inside an agent view Fixed the dim last-prompt header not appearing at the top of the conversation when scrolling up in fullscreen mode Fixed Workflow agent() calls with large output schemas being refused in auto mode instead of being checked by the safety classifier Fixed a case where a marketplace entry path containing a backslash could bypass the containment check for fetched marketplaces on macOS and Linux Fixed expired AWS or Google Cloud credentials under a host app such as Claude Desktop retrying ten times with a generic "request
Claude Code 2.1.266
September 8, 2026
Fixed a 2.1.265 regression affecting LLM-gateway and proxy setups: the undocumented CLAUDE_CODE_USE_GATEWAY environment variable, previously ignored unless ANTHROPIC_BASE_URL and ANTHROPIC_AUTH_TOKEN were both set, began forcing Cloud-gateway sign-in on its own in 2.1.265, so configurations that set it alongside an API key, apiKeyHelper, or custom auth headers failed every request with "Not signed in to the Cloud gateway". The variable on its own is ignored again; no configuration change is needed
Claude Code 2.1.265
September 8, 2026
Added user.email and user.groups to the telemetry Claude Desktop and Cowork send through a Claude apps gateway, matching terminal sessions Added support for pointing --plugin-dir at a folder of plugins: each child folder with a manifest loads, and children added or removed while running are picked up Added a 1 GB cap on tool results saved to disk; the in-conversation preview says when a saved file was truncated Fixed resuming a foreground-spawned subagent changing its tool list and system prompt prefix, which broke prompt-cache reuse for that agent Fixed agent teammates and resumed subagents moving SubagentStart hook context and preloaded skills out of the prompt prefix on later turns, which broke prompt-cache reuse Fixed resume after the previous process died while a tool was running: the last prompt is no longer rewritten, and the interrupted tool call is kept and marked interrupted Fixed /model opusplan[1m] being rejected with "Model not found" Fixed syntax-highlighted code in permission prompts and messages sometimes omitting a character after a Ruby ?, Erlang $, or Perl $ sigil Fixed the fullscreen transcript jumping by one row whenever the slash-command or @-file suggestion l
Claude Code 2.1.261
September 4, 2026
Added an "Organization policy" line to /status and claude doctor that says why your organization's policy could not be loaded, such as a proxy not passing the endpoint through Added bashOutputMaxChars and taskOutputMaxChars settings to raise how much command and background-task output Claude receives inline before it is saved to a file, up to 128K characters Added --append-subagent-system-prompt-file to read the subagent system prompt from a file, for prompts too large to pass on the command line Added /skill-doctor to show which loaded skills go unused and what they cost in context, so you can prune them Fixed typed or pasted characters occasionally landing out of order or being dropped during fast input or key repeat Fixed /add-dir printing a false "couldn't be resolved" error when the working directory is on a /net automount Fixed the Bedrock setup wizard hanging when AWS or an AWS credential helper never responds (it now times out with a clear error), and its model checks failing behind a TLS-inspecting proxy Fixed cloud sessions discarding a plugin synced from claude.ai when managed settings force-enable it in enabledPlugins, then falling back to a marketplace clone that could
Claude Code 2.1.260
September 3, 2026
Added a diff panel that opens beside the conversation in fullscreen mode and shows your uncommitted changes as Claude edits; toggle it with /diff Added a likely cause for prompt-cache misses (e.g. tool definitions or system prompt changed, idle past the TTL) to /cost and the status line's prompt_cache field Added /reload-plugins to headless sessions, so it appears in the Claude Code Desktop and SDK command lists Added a text form of /advisor (/advisor, /advisor , /advisor off) for the desktop app, Remote Control, and other headless (-p/Agent SDK) sessions Added oidc.scope_on_refresh to the Claude apps gateway for IdPs that return an id_token on refresh only when asked for openid again Added Claude apps gateway support for newer Claude Desktop keys in desktop policy blocks, including userPluginMarketplacesEnabled and userPluginUploadsEnabled Fixed Edit/Write/Read permission rules whose path contains parentheses being dropped as invalid or ignored by the Bash sandbox, which left "read-only" folders writable Fixed one file permission rule with an uncompilable pattern (e.g. an unclosed [) making every file edit fail with Invalid regular expression; such a deny rule now guards the liter
Claude Code 2.1.259
September 2, 2026
Added managedMcpServers managed setting: organizations can provide HTTP/SSE MCP servers to every user (same entry shape as .mcp.json); entries that name a command to run are skipped Added --permission-prompts none for unattended headless hosts: anything that would prompt is denied automatically while the active permission mode (including auto mode) keeps deciding Added recognition of glab mr create/merge/close/reopen/note/update so GitLab merge requests show as MR !N in the collapsed tool summary and refresh the footer MR badge Added --json to claude plugin validate for a machine-readable validation report Fixed concurrent sessions silently reverting each other's ~/.claude.json changes — workspace trust no longer resets and MCP/project state is no longer lost when running many sessions at once Fixed a conversation whose thinking was rejected once being rejected again on every later turn Fixed Bash Read() deny rules not covering files given as option values (--ignore-revs-file=.env, -f.env, @file), git diff/git grep file operands, or cd DIR && cat FILE compounds; grep -r/cp -r over a directory holding a denied file now asks Fixed the prompt cache being invalidated when the OAuth tok
Introducing Claude Fable 5.1 and Claude Mythos 5.1
September 1, 2026
via Claude
Anthropic released Claude Fable 5.1 and Claude Mythos 5.1, which it calls the world's most advanced models for coding and knowledge work. They are the same underlying model with different safeguards: Fable 5.1 is generally available, while Mythos 5.1 is limited to vetted professionals in cybersecurity and life sciences through Anthropic's access programs. Both carry a 1M-token context window, 128k max output and always-on adaptive thinking at $10 / $50 per million tokens, the same as Fable 5, with cache reads cut to $0.25 per million, about 25% cheaper in practice.
Claude Code 2.1.258
September 1, 2026
Fixed Claude Code failing to launch on macOS 12 (Monterey), a regression introduced in 2.1.255 Fixed remote and scheduled sessions failing with "user messages must have non-empty content" after a re-sent permission approval could not be applied
Claude Code 2.1.257
September 1, 2026
Added Claude Fable 5.1 (claude-fable-5-1), now the default Fable model — 1M context, 0/$50 per Mtok with $0.25/Mtok cache reads Added "Time format" (timeFormat) and timeZone settings: 12-hour, 24-hour, 24-hour UTC, or a strftime pattern for the turn-end clock and transcript-view timestamps Added a Containment Escape rule to auto mode so cloud metadata-credential fetches, egress evasion, and cross-tenant reach are no longer auto-approved unless your environment marks them expected Added CLAUDE_CODE_SUBAGENT_MODEL_FORCE to apply CLAUDE_CODE_SUBAGENT_MODEL (or the main model) to every subagent, ignoring per-spawn and agent-definition model overrides Added s in /effort to change effort for the current session only, matching /model Added a /doctor warning for stale sandbox mask files left by a killed session Added a one-time prompt in auto mode before the first file read outside the working directories, with the option to block such reads (permissions.blockReadsOutsideWorkingDirectories) Added support for a gateway-supplied description on discovered /model picker entries (CLAUDE_CODE_ENABLE_GATEWAY_MODEL_DISCOVERY); entries without one still read "From gateway" Fixed settings in a .cl
Claude Code 2.1.252
August 31, 2026
Fixed Bash commands failing with "task output swap refused (tasks dir moved or linked)" on some Macs Fixed "always allow" not saving in a project that has no .claude/settings.local.json yet Fixed Remote Control sessions hosted by Claude Desktop or VS Code stalling for minutes after a tool finished when the connection to claude.ai was degraded Fixed background task notifications with very large failure output (for example git errors on a full disk) making the conversation exceed the API request size limit
Claude Code 2.1.251
August 28, 2026
Added PreModelSwitch and PostModelSwitch hook events (block, confirm, or annotate a model switch); SessionStart resume hooks now receive session staleness and the estimated re-cache cost Added live streaming of a foreground subagent's tool calls and results to Remote Control clients (background subagents, the default, still show status only) Added a Spend limit bar to /usage and a rate_limits.spend_limit status line field for developers behind a Claude apps gateway with spend limits Added a per-session prompt-cache line to /cost (hit ratio, misses, tokens re-cached, warm/cold) and a matching prompt_cache object for status line scripts Added attach, logs, stop, respawn, and rm to claude --help; the --resume message for a running background session now names the exact claude attach command Fixed file tools (Read, Write, Edit) following a symlink swapped inside the working directory after the permission check, which could read or write outside the approved location Fixed plugin commands declared in a marketplace entry being able to point outside the plugin directory; such paths are now rejected with a path-traversal error Fixed project settings being able to enable detailed beta traci
Claude Code 2.1.248
August 27, 2026
Added --restricted (or CLAUDE_CODE_RESTRICTED=1): removes the built-in tools that run commands or code and WebFetch (unless named in --tools), keeps file tools inside the working directory, refuses bypassPermissions, and ignores user, project and local settings files Added experimental.cacheTtl ("5m" or "1h") to agent frontmatter: a per-agent prompt cache TTL used when no subagent TTL setting is configured Added claude self-hosted-runner --client-label (or SELF_HOSTED_RUNNER_CLIENT_LABEL) to override the label the runner registers with (default: hostname) Added server-managed settings diagnostics: a startup warning when the settings fail to load, and a /doctor and /status line explaining a load failure or why they weren't fetched (Bedrock/Vertex/third-party provider, custom ANTHROPIC_BASE_URL) Added a warning in /web-setup when the GitHub CLI token lacks the workflow scope, since pushes to very large repositories can be rejected without it Added /usage-credits for Enterprise organizations billed through AWS Marketplace, self-serve Enterprise, and Enterprise trials, so members can request a higher usage limit from their admin Added cross-session messaging (SendMessage / ListAgents)
Claude Code 2.1.247
August 26, 2026
Added the SendFeedback tool: when something goes wrong in a session, Claude can draft a feedback report for you to review and send from /feedback (turn off with the feedbackDrafts setting) Added {id, text, cooldownSessions, priority} entries, tipsFile, and label to spinnerTipsOverride, so organizations can rotate their own tips alongside the built-in ones Added a tip on Bash permission prompts pointing to auto mode, with a one-keystroke "Yes, and switch to auto mode" option Added /claude-api cost-optimize to profile an existing project's Claude API spend and work through cost levers (caching, token hygiene, batch, effort, model choice) one measured change at a time Updated the /claude-api skill with Admin API coverage (organization members, invites, workspaces, API keys, rate limit reports, workload identity federation, CMEK) Fixed fast arrow-key + Enter sequences acting on the row above the one you navigated to in history search, /config, /mcp, /skills, background tasks, and /model Fixed sub-agents dying on a first-call model 404: they now use the session's fallback model chain, and the error returned to the parent includes the error type, status, request id, and model Fixed a hoo
Claude Code 2.1.246
August 25, 2026
Added a startup warning for Bash allow rules with a wildcard before the subcommand (e.g. Bash(git * main)), since they also match options inserted before the subcommand Added an Auto mode tab to /permissions for viewing and editing auto mode classifier rules Added the turn's completion time to the end-of-turn duration line, e.g. ✻ Sautéed for 23s · done 6:05 PM Fixed fullscreen mode showing a blank transcript after resizing the terminal and jumping to the bottom until the next keypress Fixed a severe transcript slowdown when a diff contained a very long single line (e.g. a base64 string); such lines now render truncated with a marker Fixed erratic fullscreen scrolling when positioned at an earlier message, including jump-to-bottom getting stuck mid-transcript Fixed background sessions failing to open after 45 seconds when Claude Code's starting directory had been deleted, the machine had slept, or the host is slow to start processes Fixed background sessions failing to open with "Couldn't start the background service … EACCES" when another Claude Code process was re-installing the npm package at that moment Fixed markdown rendering being disabled for a whole message when its first
Claude Code 2.1.245
August 25, 2026
Fixed a crash on startup on Linux distributions that ship glibc 2.44 (for example Arch Linux, CachyOS and Fedora Rawhide)
Claude Code 2.1.243
August 24, 2026
Added a Loops breakdown to /usage: per-loop run count, total tokens, tokens per run, and last run, so runaway or chatty /loop tasks are easy to spot Added modelPicker setting: curate the /model picker with an ordered, labeled list of models (any id spelling, including Vertex/Bedrock ids), appended to or replacing the built-in lineup Added promptCacheTtl and subagentPromptCacheTtl settings so API-key and cloud-provider users can keep a 1-hour prompt cache on the main conversation while subagents stay at 5 minutes Added modelPricing managed setting so an organization's contracted per-model rates and discount multiplier are used for /cost, the status line, and telemetry cost figures instead of list price Added a keyless sign-in under /login → Anthropic Console: "Sign in with your Console account" (recommended) alongside creating an API key, so organizations that don't allow API keys can sign in Added a Skipped sources line to /status that lists managed settings sources (for example managed-settings.json) present but not applied because a higher-precedence managed source is active Added a managed marker in /mcp and /plugins on claude.ai connectors whose authentication is managed by you
Claude Code 2.1.239
August 21, 2026
Cost estimates (/cost, status line, --max-budget-usd) now include the 1.1× US-only-inference premium for data-residency workspaces Added the one-time fullscreen renderer offer on Bedrock, Vertex, Foundry and other previously excluded setups; new installs there now start in fullscreen Added /claude-api upgrade to migrate Python projects from anthropic 0.x to 1.x, and updated the skill's Python reference for 1.x (timeouts use anthropic.Timeout, not httpx.Timeout) Cloud sessions: plugins synced from claude.ai now show as name@synced, work with claude plugin enable/disable @synced, and never override a same-named plugin you installed Alpine/musl builds: native image paste, clipboard, and audio-capture add-ons now load (musl-built binaries instead of glibc ones refused by the runtime) The usage-limit message shown when your monthly spend limit is already used up now also says when your session or weekly limit resets Fixed Bedrock streaming behind proxies that strip the response Content-Type header, which silently doubled billed API calls by re-running every turn non-streaming Fixed Claude Code hanging at startup behind an HTTPS proxy when using Bedrock with an SSO profile and awsAuthRef
Claude Code 2.1.238
August 20, 2026
Added a keybindingFlavor setting: set it to "readline" to make Ctrl+W in the prompt delete back to the previous whitespace, as in Bash; the default ("classic") is unchanged Plugin marketplaces: headersHelper on a url marketplace or a catalog entry runs a command that mints HTTP headers (e.g. a short-lived token) for catalog and same-origin archive fetches A catalog entry's headersHelper runs only when you install or update that plugin, after its command is shown; claude plugin install/update ask [y/N] (or pass -y) Added claude self-hosted-runner --defer-shutdown-max-min : on SIGTERM, keep serving attached sessions, park what is left after that many minutes, then exit Added claude self-hosted-runner --proxy-authorization-command / --proxy-authorization-file for egress proxies that require a freshly issued Proxy-Authorization header on every connection Fixed unbounded memory growth in long interactive sessions: subagent tool results are now released once they leave the recent display window Fixed custom, project, and plugin output styles drifting back to the default voice mid-session Fixed CLAUDE_CODE_ENABLE_PROMPT_SUGGESTION=true not keeping prompt suggestions on when your account i
Claude Code 2.1.236
August 19, 2026
Added ANTHROPIC_DEFAULT_MODEL environment variable: sets the model new sessions start on, while a /model pick still overrides it and persists across restarts (unlike ANTHROPIC_MODEL) Added notify_when_idle to cross-session SendMessage: ask another Claude Code session on this machine to send one notice when it next goes idle — opt-in, one-shot, no polling (macOS and Linux) Sandbox: on macOS, wildcard read-deny rules (e.g. **/.env) now take precedence inside allowed read regions, cover matched directories' contents, and can't be bypassed by renaming the denied file Fixed clipboard copy, background housekeeping, background sessions, and local MCP logs breaking after the directory a session had switched into was removed (since 2.1.229) Fixed the fullscreen renderer failing permanently after a single failed start: it now falls back to the classic renderer instead of exiting on every subsequent launch Fixed the /model picker rendering taller than the terminal: it now shows only as many models as fit the window, with the rest reachable by scrolling Fixed SendMessage calls being rejected when a malformed closing tag left the message text inside the summary field Fixed unhandled promise rej
Claude Code 2.1.237
August 19, 2026
Fixed prompt caching for sessions using an LLM gateway or custom base URL Added a built-in "Concise" output style: Claude leads with results and skips preamble and narration, while doing the work just as thoroughly. Select it under Output style in /config.
Claude Code 2.1.235
August 18, 2026
Added an optional spellcheck setting that underlines misspelled words in the prompt input as you type, using your installed aspell, hunspell, or ispell Fixed whole-prompt-cache invalidation when a language server disconnected or reconnected mid-session Fixed nested markdown list items misaligning at depth 3+ and added a hanging indent to wrapped list items in the terminal UI Fixed prompt input highlights (slash commands, keywords, mentions) appearing shifted by one or more characters in some multi-line prompts Fixed Shift+Tab inside the permission prompt's comment field approving the edit and granting session-wide edit permission instead of closing the field Fixed the Agent tool advertising a general-purpose default in sessions where that agent is unavailable: an omitted subagent_type there now gets a clear error listing the available agents Fixed notebook cell delete/replace approval dialogs silently omitting the existing cell content when the notebook or cell could not be read; the dialog now says why Fixed slash commands run while Claude is responding showing HTML entities instead of the actual characters Fixed the prompt footer not showing the "Update installed" restart notice
Claude Code 2.1.234
August 17, 2026
Added the optional CLAUDE_CODE_PROJECT_DIR_NAME environment variable: hosts that give each session its own config directory can choose a short name for the per-project transcript directory Added the selection:clear keybinding action, so a key can be bound to clear an in-app text selection; also works in the agents view Added a GitLab merge request badge to the footer and statusline: repos with a GitLab remote and an authenticated glab CLI show MR !N with draft/pending/green states Claude Code now continues your session automatically when a claude.ai usage limit resets; turn it off in /config ("Continue automatically at usage limit") Claude is now told to use your account email only to identify you, and not to send it to unrelated services unless you ask Security: remote file reads, session restore, CLAUDE.md includes, workflow scripts and file uploads now reject Windows NT-namespace (\??\) paths, hardening the remaining pre-approval file accesses against the NTLM credential-leak vector Fixed auto mode in very long sessions repeatedly re-checking and denying sandboxed commands' network access after the conversation had been compacted Fixed session-scoped permission answers (includin