Refactor Shell Script to Google Style Guide

Refactor the specified shell script to follow Google Shell Style Guide.

Progress Tracking

Create TodoWrite with each step:

1. Identify and read target script
2. Analyze (shellcheck + shell-expert in parallel)
3. Propose changes
4. Apply refactoring
5. Verify and report

Step 1: Identify and Read Target Script

If $ARGUMENTS is provided, use it as the target script path.

Otherwise, find shell scripts and prompt user:

fd -e sh -e bash --type f 2>/dev/null | head -20

Use AskUserQuestion:

• Header: "Script"
• Question: "Which shell script would you like to refactor?"
• Options: [up to 4 scripts from fd results]

Read the script content to understand its structure.

Step 2: Analyze

Run these in parallel:

Shellcheck

shellcheck -f gcc "<target_script_path>" 2>&1 || true

If shellcheck not installed, note: brew install shellcheck (macOS) or apt install shellcheck (Linux).

Shell-expert dispatch

Task tool with:
- subagent_type: "shell:shell-expert"
- prompt: "REVIEW the shell script at <target_script_path>"

Load style guide

Skill tool with: skill: "shell:google-shell-style"

Combine findings from shellcheck and shell-expert. For each violation note:

• Line number
• Current code
• Recommended fix
• Rule reference

Step 3: Propose Changes

Present summary:

• Total violations: N
• Critical fixes: N
• Style improvements: N

Use AskUserQuestion:

• Header: "Refactor"
• Question: "How would you like to proceed?"
• Options:
  • Apply all: Apply all changes
  • Critical only: Only apply critical fixes
  • Cancel: Do not make changes

Step 4: Apply Refactoring

Use Edit tool to apply approved changes in order:

1. Critical fixes (security, correctness)
2. Structural changes (main function, organization)
3. Style improvements (formatting, quoting)

Step 5: Verify and Report

Syntax check

bash -n "<target_script_path>"

Shellcheck comparison

shellcheck -f gcc "<target_script_path>" 2>&1 || true

Compare with baseline - refactoring should reduce issues.

Final Report

## Refactoring Complete

**File:** [path]

### Changes Applied
- [key changes by category]

### Shellcheck Comparison
| Metric | Before | After | Delta |
|--------|--------|-------|-------|
| Errors | N | N | -N |
| Warnings | N | N | -N |

### Verification
- Syntax check: [PASS/FAIL]
- Shellcheck delta: [Improved/Same/Regressed]

### Shell Expert Assessment
- **Initial Review:** [summary]
- **Recommendation:** [PASS/NEEDS_FIXES]