cmd

name	cmd
description	Windows cmd.exe and batch file (.bat/.cmd) syntax for live CMD execution and batch script authoring: variables, control flow, pipes, redirection, multiline caret continuation, and copy-paste-safe blocks. Use when running cmd.exe commands, writing or editing .bat/.cmd files, Windows shell automation, or when the detected shell is cmd.exe. Replaces the external batch-files skill.

Windows CMD

cmd.exe and batch file syntax for live commands and .bat/.cmd script files. Activate via terminal/SKILL.md after context detection.

When to use

Live execution

• cmd.exe one-liners or interactive paste blocks
• Agent Shell tool commands when probe or docs indicate cmd

Script authoring

• Creating or editing .bat / .cmd files in the repo
• Windows Task Scheduler scripts, PATH-based CLI tools
• When README or probe indicates Shell: cmd

Copy-paste rules (live)

• Comments: REM (preferred) or :: — not #
• Line continuation: caret ^ as last character on line; next line continues
• No prose inside fenced blocks
• In batch files, use %% for % and %%i in FOR loops; on command line use single %

Example multiline paste (cmd.exe):

echo Line one^
 && echo Line two

Example with REM:

REM Install deps
npm install^
 && npm test

Command interpretation (summary)

1. Variable substitution — %VAR%, %0–%9, %*
2. Quoting — "path with spaces"; caret ^ escapes & | < > ^
3. Pipelines — |, &, &&, ||, ( )
4. Redirection — >, >>, <, 2>, 2>&1, >NUL

Details: syntax-reference.md

Variables (essentials)

set _MY_VAR=Hello
echo %_MY_VAR%
setlocal EnableDelayedExpansion
set /a _COUNT+=1
echo !_COUNT!
endlocal

• No spaces around = in set
• Use !VAR! inside ( ) blocks when values change at runtime
• Script directory: %~dp0

Control flow (essentials)

if exist "file.txt" echo found
if "%_A%"=="x" (echo match) else (echo no)
command1 && command2
command1 || (echo failed & exit /b 1)
for %%f in (*.txt) do echo %%f

Pipes and redirection

dir /b *.log > list.txt
command 2>&1 | findstr /i error
command >NUL 2>&1

After a pipe, triple caret may be needed to escape: echo x ^^^& y | findstr x

Inspect PATH and commands

where.exe node
where.exe git
echo %PATH%

When where finds nothing, suggest install path or set PATH=... for the session — document persistent changes with setx only when user wants that.

Admin and elevation

Prefer non-admin commands. Operations that require elevation (for example mklink /D, some reg writes):

• Detect: net session succeeds only when elevated (approximate check)
• Offer elevated variant explicitly; never run silently

See admin-windows.md.

Script structure (minimal)

@echo off
setlocal EnableDelayedExpansion
call :main %*
exit /b %ERRORLEVEL%

:main
    echo Running...
    exit /b 0

Best practices

1. @echo off + setlocal at top of scripts
2. Quote paths: "%~dp0config.ini"
3. exit /b not exit (avoid closing parent console)
4. Errors to stderr: echo ERROR: msg 1>&2
5. Prefer ROBOCOPY over legacy XCOPY

Cross-platform escape hatch

For Linux tooling on Windows, route to bash/SKILL.md (WSL2) or PowerShell — see terminal/SKILL.md.

Additional resources

• syntax-reference.md
• admin-windows.md