openclaw - 💡(How to fix) Fix Bug: exec() tool strips dollar-variable patterns via undocumented template substitution

Description

The exec() tool performs undocumented template substitution on command strings, silently stripping $variable patterns before they reach the shell.

Environment

• OS: Windows 10 (x64) on Lenovo ThinkPad P51
• OpenClaw version: 2026.5.20
• Shell: PowerShell (cmd also affected)

Steps to Reproduce

1. Call exec() with a command string containing $word patterns (e.g. $a, $start, $PSVersionTable)
2. Observe the patterns are silently removed before reaching the shell
3. Only $ at end of line passes through

Affected patterns (all fail)

• $variable is removed entirely
• Single quotes don't help: '$a' still gets stripped
• Backtick-escape does not work
• Double-dollar does not work
• cmd /c wrapper does not help (exec processes before shell)

Working workaround

Write commands to .ps1 files via write(), then execute via exec(). The %var% cmd-style env variables also pass through cleanly.

Expected

Either:

1. Pass command strings verbatim to the shell, or
2. Document the template substitution behavior