System & Runtime

HOME

• Type: String (directory path)
• Default: Auto-detected
• Description: User home directory path. Used for resolving ~ expansions and locating config directories.
• Example: /home/username

USER

• Type: String (username)
• Default: Auto-detected
• Description: Current username. Used for logging and telemetry.
• Example: myusername

USERNAME

• Type: String (username, Windows)
• Default: Auto-detected
• Description: Current username (Windows). Alternative to USER on Windows.
• Example: myusername

USERPROFILE

• Type: String (directory path, Windows)
• Default: Auto-detected on Windows
• Description: User profile directory (Windows). Alternative to HOME on Windows.
• Example: C:\Users\myusername

APPDATA

• Type: String (directory path, Windows)
• Default: Auto-detected on Windows
• Description: Application data directory (Windows). Used for config file discovery.
• Example: C:\Users\myusername\AppData\Roaming

LOCALAPPDATA

• Type: String (directory path, Windows)
• Default: Auto-detected on Windows
• Description: Local application data directory (Windows). Used for temp and cache files.
• Example: C:\Users\myusername\AppData\Local

PWD

• Type: String (directory path)
• Default: Current working directory
• Description: Current working directory. Updated automatically by the shell.
• Example: /home/user/projects/myapp

PATH

• Type: String (colon-separated paths)
• Default: System defaults
• Description: System executable search path. Used for finding executables in bash tools.
• Example: /usr/local/bin:/usr/bin:/bin

PATHEXT

• Type: String (semicolon-separated extensions, Windows)
• Default: Auto-detected on Windows
• Description: Executable file extensions (Windows). Extensions considered executable (e.g., .exe, .cmd).
• Example: .COM;.EXE;.BAT

SHELL

• Type: String (shell path)
• Default: Auto-detected
• Description: User’s default shell. Used as fallback for shell tool.
• Example: /bin/bash

LANG

• Type: String (locale identifier)
• Default: System default
• Description: System locale setting. Affects character encoding, date/time formatting, etc.
• Example: en_US.UTF-8

LC_ALL

• Type: String (locale identifier)
• Default: Unspecified
• Description: Override all locale settings. Takes precedence over individual LC_* vars.
• Example: export LC_ALL=C.UTF-8

LC_TIME

• Type: String (locale identifier)
• Default: Inherits from LANG
• Description: Time-related locale setting. Controls date/time formatting.
• Example: export LC_TIME=en_US.UTF-8

EDITOR

• Type: String (editor path or name)
• Default: Unspecified (typically nano, vi, vim)
• Description: Default text editor. Used when Claude Code needs to open an editor.
• Example: export EDITOR=vim

VISUAL

• Type: String (editor path or name)
• Default: Unspecified
• Description: Default visual editor. Takes precedence over EDITOR for graphical editing.
• Example: export VISUAL=code

BROWSER

• Type: String (browser path or name)
• Default: Auto-detected
• Description: Default browser for opening URLs. Used when Claude Code needs to open links.
• Example: export BROWSER=google-chrome

OSTYPE

• Type: String (OS identifier)
• Default: Auto-detected (linux, darwin, msys, etc.)
• Description: Operating system type identifier. Auto-detected; rarely needs override.
• Example: linux

MSYSTEM

• Type: String (MSYS2/MinGW system type)
• Default: Unspecified (set by MSYS2)
• Description: MSYS2/MinGW system type (e.g., MINGW64, MSYS). Auto-detected when using MSYS2.
• Example: MINGW64

SYSTEMROOT

• Type: String (directory path, Windows)
• Default: Auto-detected on Windows
• Description: Windows system root directory. Usually C:\Windows.
• Example: C:\Windows

SAFEUSER

• Type: String (sanitized username)
• Default: Auto-sanitized from USER
• Description: Sanitized username for safe filesystem operations. Special chars removed.
• Example: myusername

XDG_CONFIG_HOME

• Type: String (directory path)
• Default: ~/.config
• Description: XDG configuration directory. Used for config file lookup on Unix.
• Example: export XDG_CONFIG_HOME=/etc/xdg

XDG_RUNTIME_DIR

• Type: String (directory path)
• Default: Unspecified
• Description: XDG runtime directory. Used for temporary files and sockets.
• Example: /run/user/1000

DEMO_VERSION

• Type: String (version identifier)
• Default: Unspecified
• Description: Demo version identifier. Set when running in demo mode.
• Example: export DEMO_VERSION=1.0.0

IS_DEMO

• Type: Boolean (1, true, 0, false)
• Default: false
• Description: Indicates running in demo mode. Disables certain features or restrictions.
• Example: export IS_DEMO=1

IS_SANDBOX

• Type: Boolean (1, true, 0, false)
• Default: false
• Description: Indicates running inside a sandbox environment. May restrict filesystem or network access.
• Example: export IS_SANDBOX=1

SSH_CLIENT

• Type: String (connection info)
• Default: Unspecified (set by SSH daemon)
• Description: SSH client connection info. Used for remote detection. Set by ssh daemon.
• Example: 192.168.1.100 55555 22

SSH_CONNECTION

• Type: String (connection details)
• Default: Unspecified
• Description: SSH connection details. Used for remote detection.
• Example: 192.168.1.100 55555 192.168.1.50 22

SSH_TTY

• Type: String (device path)
• Default: Unspecified
• Description: SSH TTY device. Used for remote detection. Set by ssh when allocating a pseudoterminal.
• Example: /dev/pts/0

WSL_DISTRO_NAME

• Type: String (distro name)
• Default: Unspecified
• Description: WSL distribution name. Used for platform detection.
• Example: Ubuntu

STY

• Type: String (session identifier)
• Default: Unspecified
• Description: GNU Screen session identifier. Set by GNU Screen.
• Example: 12345.pts-0.hostname

VERBOSE_SSR

• Type: Boolean (1, true, 0, false)
• Default: false
• Description: Enable verbose server-side rendering logs. Development use only.
• Example: export VERBOSE_SSR=1

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