What's new in Claude Code v2.1.120

Quietly important release. Windows users no longer need Git for Windows just to run Claude Code — when Git Bash is absent, Claude Code falls back to PowerShell. claude ultrareview [target] ships as a non-interactive CLI subcommand for CI pipelines. Skills get a ${CLAUDE_EFFORT} placeholder for effort-aware authoring. AI_AGENT env var attributes subprocess traffic so gh can identify Claude Code as the originator. claude plugin validate accepts $schema, version, and description fields. DISABLE_TELEMETRY and CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC now correctly suppress usage metrics for API and enterprise users. And a critical find FD-exhaustion fix prevents host-wide crashes on macOS/Linux native builds with large directory trees.

Windows: Git for Windows no longer required

Why: Windows users previously had to install Git for Windows just to give Claude Code a POSIX shell — a confusing prerequisite for non-Git workflows.

What: When Git Bash is absent, Claude Code now uses PowerShell as the shell tool, removing the hard Git-for-Windows dependency.

How: Automatic — install Claude Code on Windows; PowerShell takes over if Git Bash isn't found.

claude ultrareview [target] for non-interactive review in CI

Why: /ultrareview was interactive-only — teams couldn't run it from CI scripts or pre-merge hooks without a TTY.

What: Adds claude ultrareview [target] subcommand that runs /ultrareview non-interactively, prints findings to stdout (--json for raw), exits 0 on completion or 1 on failure.

How: claude ultrareview path/to/file --json — drop into your CI step or git pre-push hook.

Skills can reference ${CLAUDE_EFFORT}

Why: Skills were one-size-fits-all — they couldn't adapt their depth or strictness based on the current effort level.

What: Skill content can now reference ${CLAUDE_EFFORT} to branch behavior on the active effort level.

How: Use ${CLAUDE_EFFORT} inline in your SKILL.md content; expands to the current effort level at runtime.

AI_AGENT env var for subprocess attribution

Why: Subprocesses launched by Claude Code (notably gh) couldn't attribute their traffic to the agent, blurring observability and rate-limit accounting.

What: Sets AI_AGENT environment variable for subprocesses so gh and similar tools can identify Claude Code as the originator.

How: Automatic — any subprocess Claude Code spawns inherits AI_AGENT without configuration.

claude plugin validate accepts $schema, version, description

Why: Plugin authors using JSON-schema editors and version-tracked manifests hit validation errors for fields the validator didn't recognize.

What: claude plugin validate now accepts $schema, version, and description at the top level of marketplace.json, plus $schema in plugin.json.

How: Add the fields freely to your manifests; running claude plugin validate passes without spurious errors.

DISABLE_TELEMETRY now suppresses usage metrics

Why: API and enterprise users who set DISABLE_TELEMETRY or CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC still saw usage-metrics calls leaving the host — a compliance gap.

What: Both env vars now correctly suppress usage-metrics telemetry for API and enterprise users, matching documented behavior.

How: Set DISABLE_TELEMETRY=1 — usage metrics calls are now blocked, not just telemetry events.

Critical: find no longer exhausts FDs and crashes the host

Why: On macOS/Linux native builds, the Bash tool's embedded find could exhaust open file descriptors on large trees, causing host-wide crashes — not just Claude Code crashes.

What: Reduces peak FD usage during find in the Bash tool on large directory trees, eliminating the crash path.

How: Automatic on upgrade — heavy find operations no longer take down the machine.

Hosts: Alex Chen & Sarah Kim · Generated from the official Claude Code CHANGELOG.

Full changelog: github.com/anthropics/claude-code/CHANGELOG.md

Claude Code docs: code.claude.com/docs

• (00:00) - Windows: PowerShell fallback removes Git for Windows