Changelog

Notable drops only, newest first. Dates and version numbers from the official Claude Code changelog; the full per-release list lives there. Maintained by the /content-sweep Lane C.

2026-08-21: /claude-api upgrade and honest cost math (2.1.239)

New /claude-api upgrade migrates Python projects from anthropic 0.x to 1.x. Cost surfaces (/cost, the status line, --max-budget-usd) now include the 1.1x US-only-inference premium for data-residency workspaces, so caps reflect what you actually pay. Fullscreen renderer now also offered on Bedrock, Vertex, and Foundry setups.

2026-08-20: Concise output style ships built in (2.1.237)

A new "Concise" style under Output style in /config: Claude leads with results and skips preamble and narration while doing the work just as thoroughly. Same release fixes prompt caching for LLM-gateway and custom-base-URL sessions. 2.1.238 adds keybindingFlavor: "readline" (Bash-style Ctrl+W) and plugin-marketplace headersHelper for minting short-lived auth headers.

2026-08-19: Default-model env var and idle notifications (2.1.236)

ANTHROPIC_DEFAULT_MODEL sets the model new sessions start on while /model picks still win. Cross-session SendMessage gains notify_when_idle: ask another session on the machine to ping you once when it next goes idle, no polling. macOS sandbox wildcard read-deny rules (like **/.env) now hold inside allowed regions and survive file renames.

2026-08-17: Sessions continue themselves at limit reset (2.1.234)

Claude Code now continues your session automatically when a claude.ai usage limit resets (toggle in /config). GitLab lands as a first-class remote: MR badge in the footer and status line (2.1.234), plus --worktree MR support and opt-in Bash memory cgroups on Linux (2.1.233).

2026-08-14: Auto mode becomes the default (Pro, Max, Team)

New sessions start in auto mode: a classifier judges each action and blocks the dangerous ones instead of prompting you for everything. Anthropic's numbers: the classifier blocked 89% of dangerous commands in a 1,053-tester study versus 13.6% caught by manual approval, and production-severity unintended actions fell from 6.3% of manually approved sessions to 2.4%. Shift+Tab still cycles modes; admins can pin defaultMode or set disableAutoMode. Enterprise and cloud-platform rollout follows. Classifier overhead is no longer billed on Pro/Max/Team.

2026-08-13: Subagent forking on by default (2.1.232)

subagent_type: "fork" subagents inherit the full conversation and prompt cache, and non-teammate agent spawns in interactive sessions now run in the background by default. Type @ in the prompt to mention another live Claude session by name and message it directly. Sessions on one machine now keep unique names.

2026-08-07: Self-hosted runners (2.1.224)

claude self-hosted-runner turns your own machines or containers into a place Claude Code web, mobile, and desktop sessions can run (Team and Enterprise). Plugins gain an archive source: install from a zip over HTTPS with optional SHA-256 pinning, no git or npm. 2.1.229 documents claude remote-control --continue and adds marketplace command sources.

2026-08-04: Sandbox credential masking and permission hardening (2.1.221)

Sandbox credential files get mode: "mask" on Linux/WSL: commands read a sentinel while the proxy substitutes the real value on egress. VSCode gains the Focus view (Ctrl+Alt+F). A new prompt-audit subcommand ships. The two follow-ups matter for safety: 2.1.222 stops worktree-isolated sessions running destructive git against the main checkout, and 2.1.223 closes a Bash permission bypass where crafted or invisible-Unicode commands could hide from permission checks.

2026-07-24: Claude Opus 5 becomes the default Opus (2.1.219)

Opus 5 ships as the default Opus model, with a 1M context window and fast mode at $10/$50 per Mtok. Subagents can spawn nested subagents up to depth 3 again, after 2.1.217 cut the default to

1. New sandbox.network.strictAllowlist denies non-allowlisted hosts for sandboxed commands without prompting, and a workflowSizeGuideline settings key sets the dynamic workflow size guideline from any settings file. Opus 4.7 loses fast mode, so /fast now covers Opus 5 and 4.8.

2026-07-22: /code-review moves to a background subagent (2.1.218)

Review work no longer fills your conversation. Skills with context: fork now run in the background by default; opt out per skill with background: false. Agent frontmatter hooks now require the agent file's own folder to have accepted workspace trust, and /deep-research starts only when you invoke it rather than launching on its own.

2026-07-21: Subagent concurrency and budget caps (2.1.217)

Concurrent subagents are capped at 20 by default, overridable with CLAUDE_CODE_MAX_CONCURRENT_SUBAGENTS, so a single message cannot fan out unbounded background agents. --max-budget-usd now actually halts background subagents once the cap is reached instead of letting them run on past it. Also fixes a memory leak where truncated MCP tool output kept the full untruncated result in memory for the rest of the session.

2026-07-20: Long-session slowdown fix (2.1.216)

Message normalization cost grew quadratically with the number of turns, causing multi-second stalls and slow resumes in long sessions. New sandbox.filesystem.disabled setting skips filesystem isolation while keeping network egress control. Worktree-isolated subagents can no longer redirect git into the shared checkout via git -C, --git-dir, or GIT_DIR.

2026-06-12: Conversation-language session titles (2.1.176)

Session titles are now generated in the language of your conversation. New footerLinksRegexes setting renders regex-matched link badges in the footer row; improved Bedrock credential caching.

2026-06-08: --safe-mode + /cd (2.1.169)

New --safe-mode flag for a locked-down launch; /cd moves a session to a new working directory mid-run; self-hosted runner gains a post-session lifecycle hook.

2026-06-06: Configurable fallback models (2.1.166)

fallbackModel setting tries up to three models in order when the primary is overloaded or unavailable (--fallback-model now applies to interactive sessions too). Finer thinking controls (MAX_THINKING_TOKENS=0, --thinking disabled), plus MCP and cross-session messaging hardening.

2026-06-04: /plugin list + managed version ranges (2.1.163)

Plugin listing with --enabled/--disabled filters; requiredMinimumVersion / requiredMaximumVersion managed settings to pin a Claude Code version range; Stop and SubagentStop hooks can now return additionalContext.

2026-06-03: Remote Control footer + agent-view waitingFor (2.1.162)

Remote Control shows as a persistent footer pill instead of a startup message; claude agents --json exposes what a session is blocked on; glob patterns supported in deny-rule tool names.

2026-05-29: Plugins auto-load from .claude/skills (2.1.157)

Plugins placed in .claude/skills load with no marketplace; claude plugin init <name> scaffolds a new plugin; EnterWorktree can switch between Claude-managed worktrees mid-session.

2026-05-28: Opus 4.8 + dynamic workflows (2.1.154)

Opus 4.8 ships and defaults to high effort (/effort xhigh); Fast mode on 4.8 runs ~2× the standard rate for ~2.5× the speed. Dynamic workflows arrive: ask Claude to orchestrate work across tens to hundreds of background agents and run /workflows to view runs. The trigger keyword was renamed workflow to ultracode. Background command execution via claude --bg --exec.

2026-05-27: /code-review --fix + skill controls (2.1.152)

/code-review --fix applies review findings to the working tree and /simplify invokes it; skills can declare disallowed-tools; added /reload-skills and a MessageDisplay hook.

2026-05-21: Pinned background sessions; /simplify → /code-review (2.1.147)

Pinned background sessions stay alive when idle and restart in place across updates; the review commands consolidate under /code-review; EnterWorktree branches from local HEAD.

2026-05-19: /model session-scoped + background resume (2.1.144)

/model now changes the current session only (press d to set the default for new sessions); claude --bg sessions appear in /resume, marked bg.

2026-05-11: Agent view (research preview) + /goal (2.1.139)

claude agents lists every session (running, blocked, done); /goal sets a completion condition and Claude keeps working until it's met, with a live elapsed/turns/tokens overlay.

2026-05-06: Code with Claude: Remote Control, proactive workflows, managed agents

Anthropic previews cross-device Remote Control, routines that run on cron schedules / GitHub webhooks / API endpoints, and Claude Managed Agents (sandboxed execution, checkpointing, credential scoping).