Bash Scripter Skill

Bash is the language most developers use reluctantly and most sysadmins use constantly. The syntax is unforgiving, the edge cases are numerous, and the error messages are often useless. This skill writes correct Bash on the first attempt and explains what every part does.

What the skill does

• Script generation. Writes complete Bash scripts from a plain-language description of what the script should do.
• Error handling. Includes set -euo pipefail, proper exit codes, and meaningful error messages — not scripts that fail silently.
• Argument parsing. getopts-based argument handling with usage messages, required argument checks, and defaults.
• Logging. Timestamped log output with severity levels — useful for scripts that run unattended in cron or CI.
• Debugging. Fixes broken scripts and explains why they were broken — quoting issues, word splitting, subshell variable scope, and other classic Bash traps.
• One-liners. Constructs complex find, awk, sed, and grep pipelines from a plain description of the transformation needed.
• Compatibility. Notes where scripts use bash-specific features and provides POSIX-compatible alternatives when cross-shell compatibility matters.

How it works

1. Describe the task. What should the script do? What inputs does it take? What should it output or change?
2. Specify the environment. Linux distro, Bash version, whether it will run interactively or in cron/CI.
3. Script draft. A complete, commented script with error handling built in.
4. Explanation. Ask the skill to walk through any part of the script in plain language.
5. Iteration. Ask to add a flag, handle a new case, or make the script more defensive.

How to use it

1. Click ⬇ Download this Claude Skill above.
2. Import through Claude Desktop (Customize → Skills → + → Create skill → Upload a skill) or drop into .claude/commands/. Full walkthrough in the import tutorial.
3. Invoke the skill:

   /bash-scripter
   

   Or describe the task directly:

   /bash-scripter Write a script that backs up a directory to S3, keeps the last 7 backups, and sends a Slack notification on failure. Runs from cron on Ubuntu 22.04.
   

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Quick-start prompt (no download)

Write a Bash script that does the following: [describe what you need]

Requirements:

• Use set -euo pipefail at the top so the script fails fast and loudly
• Accept arguments with getopts and show a usage message if required arguments are missing
• Include timestamped logging (INFO / ERROR levels) that works unattended in cron
• Handle errors with meaningful messages — no silent failures
• Add comments for any non-obvious line

Environment: [Linux distro and Bash version, or "must be POSIX-compatible"] Runs: [interactively / from cron / from a CI pipeline]

[If debugging an existing script, paste it here with the error output]

Tips:

• Always quote your variables: "$var" not $var — unquoted variables break in filenames with spaces.
• Ask the skill to explain what set -euo pipefail does and why each flag matters — it is the most important thing to understand about defensive Bash.
• For one-liners that process text, describe the input format and what the output should look like — the skill constructs the awk/sed pipeline for you.
• Use SysEmperor's Cron Visual Editor to build and validate the cron schedule expression before wiring it to your script.

⚠ This skill has been tested and optimized for Claude. Results may vary with other AI assistants.