Claude Code v2.1.120 / Changelog

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23 entries

Changesopen

`claude ultrareview` CLI Subcommand #

What

Run a cloud-hosted multi-agent code review directly from the command line, without entering an interactive session.

Usage

claude ultrareview              # review current branch
claude ultrareview 42           # review PR #42
claude ultrareview main         # review against a base branch
claude ultrareview --json       # print raw bugs.json payload
claude ultrareview --timeout 45 # wait up to 45 minutes (default: 30)

Details

Launches a remote multi-agent session that finds and verifies bugs in your branch
Prints live progress (found, verified, refuted counts) to stderr while waiting
Outputs formatted findings with file paths, line numbers, and severity (🔴 normal, 🟡 nit, 🟣 pre-existing)
Ctrl-C cancels the wait but leaves the remote review running — a URL is printed so you can view it in the browser
The /ultrareview slash command existed previously; this adds it as a top-level CLI entry point

Evidence

CLI command registered via .command("ultrareview [target]") with .description("Run a cloud-hosted multi-agent code review...") — search for "ultrareview [target]"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Lean Prompt Mode (Condensed Tool Descriptions)#

Feature flag

tengu_vellum_lantern Off in both readings

The flag server returned off for the account this site reads and for the anonymous baseline. A reading of off cannot rule out a rollout these two readings sit outside of.

This account: off · anonymous baseline: off · compiled default in v2.1.120: no gate table built for this version

These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.

Read once, for one account on one subscription tier, against v2.1.120. It isn't a statement about your account. What a flag value here can and cannot tell you

What

A new prompt optimization mode that significantly reduces system prompt token usage by sending shorter, denser tool descriptions to capable models.

Usage

CLAUDE_CODE_LEAN_PROMPT=1 claude   # force enable via env var

Details

When active, tool descriptions for Grep, Glob, WebFetch, Write, Edit, WebSearch, TodoWrite, Bash, and the Task/Explore agent are replaced with much shorter versions
Example: the Grep tool description goes from a multi-paragraph usage guide to a compact 4-line summary
The Explore agent description is refined to emphasize it is a "read-only search agent" not suitable for code review or cross-file analysis
Activated by the CLAUDE_CODE_LEAN_PROMPT environment variable, or gradually rolled out via the tengu_vellum_lantern feature flag
Currently limited to Opus 4.6+ and Opus 4.7 models

Evidence

Lean prompt gate function checks CLAUDE_CODE_LEAN_PROMPT and tengu_vellum_lantern — search for "CLAUDE_CODE_LEAN_PROMPT"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Memory Write Confirmation Dialog #

Feature flag

tengu_slate_siskin Not enough to say

Nothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.

This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.120: no gate table built for this version

These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.

Read once, for one account on one subscription tier, against v2.1.120. It isn't a statement about your account. What a flag value here can and cannot tell you

What

When Claude writes or edits a memory file, a confirmation dialog now appears showing what was saved, with the option to approve or reject the change.

Details

Shows "Memory written" or "Memory updated" with a preview of the content (or a one-sentence AI-generated summary for large memories)
For edits, displays a diff view; for new memories, displays the body text
Auto-hides after a configurable timeout (default 8 seconds) with a countdown indicator
Rejecting a memory write undoes the file change (restores the previous content or deletes the file)
The summary is generated by Sonnet 4.6 for memories exceeding a line threshold (default: 5 lines)
Controlled by the tengu_slate_siskin feature flag (disabled by default)

Evidence

Memory write survey infrastructure with approve/reject dialog — search for "memoryWriteSurvey" and "tengu_slate_siskin"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

`memory-types` Skill #

What

A new internal skill that provides a full reference for the memory type taxonomy — what each type captures, when to save it, and how to structure the body.

Details

Not user-invocable directly; Claude uses it automatically before writing a memory file when lean prompts are active
Enabled when tengu_ochre_finch flag is active or CLAUDE_CODE_LEAN_PROMPT is set
Replaces the longer inline memory documentation in the system prompt with a shorter summary plus a skill reference
The system prompt now lists memory types as a compact bulleted list and says "Invoke the memory-types skill for scope, body structure and examples"

Evidence

Skill registered as "memory-types" with userInvocable: !1 — search for "memory-types"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Daemon Cold-Start Service Installation Prompt #

Feature flag

tengu_quiet_harbor Off in both readings

The flag server returned off for the account this site reads and for the anonymous baseline. A reading of off cannot rule out a rollout these two readings sit outside of.

This account: off · anonymous baseline: off · compiled default in v2.1.120: no gate table built for this version

These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.

Read once, for one account on one subscription tier, against v2.1.120. It isn't a statement about your account. What a flag value here can and cannot tell you

What

When no background daemon is running and one is needed, Claude Code now interactively asks whether to install it as a persistent system service.

Usage

No background daemon is running.
Installing it as a service keeps scheduled and remote-control workers running across reboot.
Install as a service now? [Y/n/never, or 'once' for this login session]

Details

Y (default): installs a launchd (macOS) or systemd (Linux) service that persists across reboot
once: spawns a transient daemon for the current login session only
never: remembers the dismissal and won't ask again (spawns transient)
n: does nothing — the command fails with the original "no daemon running" error
Controlled by the tengu_quiet_harbor feature flag (determines whether mode is "ask" or "transient")
Also configurable via CLAUDE_CODE_DAEMON_COLD_START environment variable or settings.daemonColdStart
The daemon auto-uninstalls stale service files that were not created by the current version (tagged with claude-managed: v1)

Evidence

Interactive prompt with "Install as a service now? [Y/n/never, or 'once' for this login session]" — search for that string, gated by tengu_quiet_harbor

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Chrome Extension: `tabs_close_mcp` Tool #

What

A new MCP tool that lets Claude close individual tabs in the Chrome tab group by ID.

Details

Only tabs in the current session's tab group are closable
Call tabs_context_mcp first to get valid tab IDs
If you close the group's last tab, Chrome auto-removes the group — the next tabs_context_mcp with createIfEmpty starts fresh
Replaces the previous update_plan tool that was used in the Chrome extension's plan-approval flow

Evidence

Tool registered as "tabs_close_mcp" with title "Tabs Close" — search for "tabs_close_mcp"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

User Deny Rules Awareness in System Prompt #

What

Claude is now informed about the user's configured permission deny rules and instructed to block circumvention attempts.

Details

The system prompt now includes a section listing all active deny rules
Claude is instructed to block actions that achieve the same effect via a different tool — e.g., using python -c, sed -i, cat >, heredocs, or similar to write a file that an Edit/Write deny rule covers
Only non-internal deny rules are surfaced (rules starting with a specific internal prefix are filtered out)

Evidence

New function builds deny rule text: "User Deny Rules: The user has configured these permission deny rules..." — search for "User Deny Rules"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

`hideVimModeIndicator` Status Line Setting #

What

A new boolean setting to suppress the built-in -- INSERT -- / -- VISUAL -- vim mode indicator below the prompt.

Usage (in settings):

{
  "statusLine": {
    "hideVimModeIndicator": true
  }
}

Details

Use this when your custom status line script already renders vim.mode itself
Prevents duplicate mode indicators when using a custom status line

Evidence

New setting hideVimModeIndicator with .describe("Hide the built-in...") — search for "hideVimModeIndicator"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

`CLAUDE_EFFORT` System Prompt Substitution #

What

A new ${CLAUDE_EFFORT} template variable is now available in system prompts, dynamically resolved from the session's effort setting.

Details

The variable is interpolated during session initialization
Allows system prompts to adapt behavior based on the current effort level

Evidence

Template variable ${CLAUDE_EFFORT} appears in system prompt processing — search for "CLAUDE_EFFORT"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Renamed "Bash Mode" to "Shell Mode"#

The ! prefix hint has been renamed from "bash mode" to "shell mode" to reflect the broader shell support now available (bash, zsh, sh, and PowerShell on Windows).

Evidence

String changed from "! for bash mode" to "! for shell mode" — search for "! for shell mode"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

Expanded Windows PowerShell Integration #

PowerShell support on Windows has been improved with smarter shell selection and better error handling:

Shell selection now falls back gracefully: if defaultShell is set to "bash" but Git Bash isn't installed, PowerShell is used instead, and vice versa
The shell setting description now reads "Defaults to bash (powershell on Windows without Git Bash)"
Clipboard operations on Windows now use proper argument arrays instead of concatenated strings for safer command execution
Clear error messages guide users when neither Git Bash nor PowerShell is available:
"Claude Code on Windows requires either Git for Windows (for bash) or PowerShell"
Hook errors now suggest "Install Git for Windows, or add shell: powershell to this hook's config"

Evidence

Shell fallback logic in g24() function — search for "Git Bash not found" and "CLAUDE_CODE_USE_POWERSHELL_TOOL"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Improved Scroll Wheel Notification #

The scroll wheel arrow-key detection now suggests a simpler fix. The notification has been changed from "run /terminal-setup to fix" to "use PgUp/PgDn to scroll", removing the need for users to run a separate command.

Evidence

String changed from "run /terminal-setup to fix" to "use PgUp/PgDn to scroll" — search for "PgUp/PgDn to scroll"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

v2.1.116 Scroll Wheel Terminal Hint

Improved Autocompact Notification #

The autocompact notification has been refined:

Message changed from "compacted at the auto window (N tokens)" to "compacting at the auto N window · configure with /autocompact"
Notification priority changed from "medium" to "immediate" for better visibility
Now uses the "suggestion" color theme and a 12-second timeout

Evidence

Notification text updated — search for "compacting at the auto" and "configure with /autocompact"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

v2.1.121 Autocompact Status Display

Better Exit/Detach Labels for Remote Sessions #

When running as a background/remote session with active tasks, the Escape exit message now shows "detach (session keeps running)" instead of "stop session", making it clearer that background work continues after detaching.

Evidence

Dynamic label logic — search for "detach (session keeps running)" and "stop session"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

Richer Tool-Call Labels in Status Display #

AskUserQuestion prompts and Plan-mode submissions now show descriptive labels in the status display:

Questions show the header/question text (e.g., "Question: Which library?" or "Tap to answer")
Plan submissions show "Plan ready for review"

Evidence

Label rendering logic — search for "Tap to answer" and "Plan ready for review"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Hidden Message Count in Focused Mode #

When messages are hidden due to /focus mode, the prompt now displays a count like "3 messages hidden (/focus to show)" to help users know when context has been abbreviated.

Evidence

New label format — search for "hidden (/focus to show)"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Graceful Marketplace Plugin Degradation #

Plugins with unrecognized source types are now stubbed rather than dropped entirely:

If a marketplace plugin entry uses a source type not supported by the current Claude Code version, it is preserved as an "unsupported" placeholder
Installation attempts fail with a clear "update Claude Code and try again" message
This prevents detectDelistedPlugins from incorrectly treating it as removed

Evidence

Plugin stubbing logic — search for "Stubbing unparseable marketplace plugin entry" and "source.source: 'unsupported'"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Daemon CLI Enhancements #

The claude daemon subcommand has been reorganized with new operations:

New hub subcommand for interactive daemon management (requires TTY)
New list subcommand for a flat view across all worker kinds
New scheduled, assistant, remote-control subcommands for per-kind listing and mutation
start and restart subcommands are now explicitly disabled with a clear message: "the daemon runs on demand and exits when the last client disconnects"
stop --any can now stop transient (non-service) daemons
Better status output including pid, version, uptime, origin, and config path
Auto-uninstalls stale service files from previous Claude Code versions

Evidence

Help text registered as "Usage: claude daemon [subcommand] [options]..." — search for that string

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Improved Explore Agent Description #

The Explore (search) agent description has been rewritten to be more precise about its limitations: it is now described as a "read-only search agent" that should NOT be used for "code review, design-doc auditing, cross-file consistency checks, or open-ended analysis" since it "reads excerpts rather than whole files and will miss content past its read window."

Evidence

New description string — search for "read-only search agent"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Feedback Submission Now Tracks Surface Origin #

The /feedback submission now records the surface field (e.g., "cli") to distinguish reports from different Claude Code surfaces (terminal, CCD, CCW). This helps the triage pipeline route reports correctly.

Evidence

surface parameter in feedback payload — search for "Where the feedback flow was initiated"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

File Watcher Error Handling #

Multiple subsystems now log warnings on file watcher errors instead of crashing:

[settings] watcher error: for settings file changes
[skills] watcher error: for skill file changes
[theme] watcher error: for theme file changes
[jobStateNameSync] watcher error: for job state changes
[useBgSessionPr] watcher error: for background session PR changes
FileChanged: watcher error: for general file change detection

Evidence

Search for "watcher error:" in the string diff

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Agent Auto-Relaunch Tracking #

A new CLAUDE_AGENTS_AUTO_RELAUNCHED_AT environment variable is set when an agent is automatically relaunched, allowing detection and prevention of relaunch loops.

Evidence

New env var — search for "CLAUDE_AGENTS_AUTO_RELAUNCHED_AT"

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Username Validation #

The getUsername() function now validates the system username against a safe regex pattern and falls back to "claude-code-user" if it contains unexpected characters, preventing potential issues with unusual usernames.

Evidence

Username validation with regex test — function xe() at line ~104573

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

4 entries

Bug Fixesopen

#

Fixed Chrome extension ToolCallTimeoutError and ExtensionDisconnectedMidCallError — new error types provide more specific messaging when the Chrome extension disconnects mid-operation or times out (search for "ExtensionDisconnectedMidCallError")
Fixed daemon stop on Windows: the error message now correctly advises using taskkill /PID instead of attempting signals that Windows doesn't support (search for "taskkill /PID")
Fixed worktree cleanup handling: uncommitted changes in agent worktrees are now preserved with a warning rather than silently lost (search for "changed file(s) would be lost, kept")
Fixed autocompact thrashing detection: the thrashing message now properly triggers on repeated rapid re-compactions (search for "Autocompact is thrashing")
Fixed auth token refresh: proactive token refresh failures are now logged and retried with a 60-second delay instead of failing silently (search for "auth: proactive refresh failed")
Fixed plan-mode blocking: the post_turn_summary now correctly maps "blocked" status to "need_input" for plan mode flows (search for "status_category")

Lean Prompt System [Gradual Rollout]#

Feature flag

tengu_vellum_lantern Off in both readings

The flag server returned off for the account this site reads and for the anonymous baseline. A reading of off cannot rule out a rollout these two readings sit outside of.

This account: off · anonymous baseline: off · compiled default in v2.1.120: no gate table built for this version

These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.

Read once, for one account on one subscription tier, against v2.1.120. It isn't a statement about your account. What a flag value here can and cannot tell you

What

The full lean prompt system that compresses all tool descriptions and system prompt content for reduced token usage.

Status

Feature-flagged behind tengu_vellum_lantern (default false), overridable with CLAUDE_CODE_LEAN_PROMPT=1.

Details

Currently restricted to Opus 4.6+ and Opus 4.7 models
The tengu_ochre_finch flag controls lean memory prompts independently
When fully enabled, tool descriptions are 60-80% shorter while preserving essential usage information
Users can preview it now via the environment variable

Memory Write Confirmation [Gradual Rollout]#

Feature flag

tengu_slate_siskin Not enough to say

Nothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.

This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.120: no gate table built for this version

These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.

Read once, for one account on one subscription tier, against v2.1.120. It isn't a statement about your account. What a flag value here can and cannot tell you

What

The interactive approve/reject dialog for memory file writes.

Status

Feature-flagged behind tengu_slate_siskin (default false), with configurable timeout, throttle, and summary threshold.

Details

Full UI infrastructure is in place including diff rendering, AI-powered summaries, and undo capability
Configurable via the feature flag's schema: enabled, timeoutMs (1000-120000), throttleMs (0-3600000), summaryLineThreshold (1-50)
When enabled, every memory write surfaces a brief confirmation with countdown timer

Daemon Service Cold-Start Prompt [Gradual Rollout]#

Feature flag

tengu_quiet_harbor Off in both readings

The flag server returned off for the account this site reads and for the anonymous baseline. A reading of off cannot rule out a rollout these two readings sit outside of.

This account: off · anonymous baseline: off · compiled default in v2.1.120: no gate table built for this version

These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.

Read once, for one account on one subscription tier, against v2.1.120. It isn't a statement about your account. What a flag value here can and cannot tell you

What

Interactive prompt to install the daemon as a persistent system service.

Status

Feature-flagged behind tengu_quiet_harbor (default false — defaults to "transient" mode where daemon spawns on demand without asking).

Details

When the flag is enabled (set to return "ask"), the interactive installation prompt appears
Can be forced via CLAUDE_CODE_DAEMON_COLD_START=ask environment variable or settings.daemonColdStart

Claude Code v2.1.120

Changesopen

`claude ultrareview` CLI Subcommand #

Lean Prompt Mode (Condensed Tool Descriptions)#

Memory Write Confirmation Dialog #

`memory-types` Skill #

Daemon Cold-Start Service Installation Prompt #

Chrome Extension: `tabs_close_mcp` Tool #

User Deny Rules Awareness in System Prompt #

`hideVimModeIndicator` Status Line Setting #

`CLAUDE_EFFORT` System Prompt Substitution #

Renamed "Bash Mode" to "Shell Mode"#

Related

Expanded Windows PowerShell Integration #

Improved Scroll Wheel Notification #

Related

Improved Autocompact Notification #

Related

Better Exit/Detach Labels for Remote Sessions #

Related

Richer Tool-Call Labels in Status Display #

Hidden Message Count in Focused Mode #

Graceful Marketplace Plugin Degradation #

Daemon CLI Enhancements #

Improved Explore Agent Description #

Feedback Submission Now Tracks Surface Origin #

File Watcher Error Handling #

Agent Auto-Relaunch Tracking #

Username Validation #

Related

Bug Fixesopen

#

Lean Prompt System [Gradual Rollout]#

Memory Write Confirmation [Gradual Rollout]#

Daemon Service Cold-Start Prompt [Gradual Rollout]#

Anthropic’s official release notes