Disk Hygiene
Audit disk usage, clean developer caches, find forgotten large files, and triage Downloads on macOS.
Self-Evolving Skill: This skill improves through use. If instructions are wrong, parameters drifted, or a workaround was needed — fix this file immediately, don't defer. Only update for real, reproducible issues.
When to Use This Skill
Use this skill when:
- User asks about disk space, storage, or cleanup
- System is running low on free space
- User wants to find old/forgotten large files
- User wants to clean developer caches (brew, uv, pip, npm, cargo)
- User wants to triage their Downloads folder
- User asks about disk analysis tools (dust, dua, gdu, ncdu)
TodoWrite Task Templates
Template A - Full Disk Audit
1. Run disk overview (df -h / and major directories)
2. Audit developer caches (uv, brew, pip, npm, cargo, rustup, Docker)
3. Scan for forgotten large files (>50MB, not accessed in 180+ days)
4. Present findings with AskUserQuestion for cleanup choices
5. Execute selected cleanups
6. Report space reclaimed
Template B - Cache Cleanup Only
1. Measure current cache sizes
2. Run safe cache cleanups (brew, uv, pip, npm)
3. Report space reclaimed
Template C - Downloads Triage
1. List Downloads contents with dates and sizes
2. Categorize into groups (media, dev artifacts, personal docs, misc)
3. Present AskUserQuestion multi-select for deletion/move
4. Execute selected actions
Template D - Forgotten File Hunt
1. Scan home directory for large files not accessed in 180+ days
2. Group by location and type (media, ISOs, dev artifacts, documents)
3. Present findings sorted by size
4. Offer cleanup options via AskUserQuestion
Phase 1 - Disk Overview
Get the lay of the land before diving into specifics.
/usr/bin/env bash << 'OVERVIEW_EOF'
echo "=== Disk Overview ==="
df -h /
echo ""
echo "=== Major Directories ==="
du -sh ~/Library/Caches ~/Library/Logs ~/Library/Application\ Support \
~/.Trash ~/Downloads ~/Documents ~/Desktop ~/Movies ~/Music ~/Pictures \
2>/dev/null | sort -rh
echo ""
echo "=== Developer Tool Caches ==="
du -sh ~/.docker ~/.npm ~/.cargo ~/.rustup ~/.local ~/.cache \
~/.conda ~/.pyenv ~/.local/share/mise 2>/dev/null | sort -rh
OVERVIEW_EOF
Phase 2 - Cache Audit & Cleanup
Cache Size Reference
| Cache | Location | Typical Size | Clean Command |
| ----------- | ----------------------------------- | ------------ | ----------------------------------------- |
| uv | ~/Library/Caches/uv/ | 5-15 GB | uv cache clean |
| Homebrew | ~/Library/Caches/Homebrew/ | 3-10 GB | brew cleanup --prune=all |
| pip | ~/Library/Caches/pip/ | 0.5-2 GB | pip cache purge |
| npm | ~/.npm/_cacache/ | 0.5-2 GB | npm cache clean --force |
| cargo | ~/.cargo/registry/cache/ | 1-5 GB | cargo cache -a (needs cargo-cache) |
| rustup | ~/.rustup/toolchains/ | 2-8 GB | rustup toolchain remove <old> |
| Docker | Docker.app | 5-30 GB | docker system prune -a |
| Playwright | ~/Library/Caches/ms-playwright/ | 0.5-2 GB | npx playwright uninstall |
| sccache | ~/Library/Caches/Mozilla.sccache/ | 1-3 GB | rm -rf ~/Library/Caches/Mozilla.sccache |
| huggingface | ~/.cache/huggingface/ | 1-10 GB | rm -rf ~/.cache/huggingface/hub/<model> |
Safe Cleanup Commands (Always Re-downloadable)
/usr/bin/env bash << 'CACHE_CLEAN_EOF'
set -euo pipefail
echo "=== Measuring current cache sizes ==="
echo "uv: $(du -sh ~/Library/Caches/uv/ 2>/dev/null | cut -f1 || echo 'N/A')"
echo "Homebrew: $(du -sh ~/Library/Caches/Homebrew/ 2>/dev/null | cut -f1 || echo 'N/A')"
echo "pip: $(du -sh ~/Library/Caches/pip/ 2>/dev/null | cut -f1 || echo 'N/A')"
echo "npm: $(du -sh ~/.npm/_cacache/ 2>/dev/null | cut -f1 || echo 'N/A')"
echo ""
echo "=== Cleaning ==="
brew cleanup --prune=all 2>&1 | tail -3
uv cache clean --force 2>&1
pip cache purge 2>&1
npm cache clean --force 2>&1
CACHE_CLEAN_EOF
Troubleshooting Cache Cleanup
| Issue | Cause | Solution |
| ----------------------------------- | -------------------------- | ----------------------------------------- |
| uv cache lock held | Another uv process running | Use uv cache clean --force |
| brew cleanup skips formulae | Linked but not latest | Safe to ignore, or brew reinstall <pkg> |
| pip cache purge permission denied | System pip vs user pip | Use python -m pip cache purge |
| Docker not running | Docker Desktop not started | Start Docker.app first, or skip |
Phase 3 - Forgotten File Detection
Find large files that have not been accessed in 180+ days.
/usr/bin/env bash << 'STALE_EOF'
echo "=== Large forgotten files (>50MB, untouched 180+ days) ==="
echo ""
# Scan home directory (excluding Library, node_modules, .git, hidden dirs)
find "$HOME" -maxdepth 4 \
-not -path '*/\.*' \
-not -path '*/Library/*' \
-not -path '*/node_modules/*' \
-not -path '*/.git/*' \
-type f -atime +180 -size +50M 2>/dev/null | \
while read -r f; do
mod_date=$(stat -f '%Sm' -t '%Y-%m-%d' "$f" 2>/dev/null)
size=$(du -sh "$f" 2>/dev/null | cut -f1)
echo "${mod_date} ${size} ${f}"
done | sort
echo ""
echo "=== Documents & Desktop (>10MB, untouched 180+ days) ==="
find "$HOME/Documents" "$HOME/Desktop" \
-type f -atime +180 -size +10M 2>/dev/null | \
while read -r f; do
mod_date=$(stat -f '%Sm' -t '%Y-%m-%d' "$f" 2>/dev/null)
size=$(du -sh "$f" 2>/dev/null | cut -f1)
echo "${mod_date} ${size} ${f}"
done | sort
STALE_EOF
Common Forgotten File Types
| Type | Typical Location | Example |
| --------------------- | -------------------- | ---------------------------- |
| Windows/Linux ISOs | Documents, Downloads | .iso files from VM setup |
| CapCut/iMovie exports | Movies/ | Large .mp4 renders |
| Phone video transfers | Pictures/, DCIM/ | .MOV files from iPhone |
| Old Zoom recordings | Documents/ | .aac, .mp4 from meetings |
| Orphaned downloads | Documents/ | CFNetworkDownload_*.mp4 |
| Screen recordings | Documents/, Desktop/ | Capto/QuickTime .mov |
Phase 4 - Downloads Triage
Use AskUserQuestion with multi-select to let the user choose what to clean.
Workflow
- List all files in
~/Downloadswith dates and sizes - Categorize into logical groups
- Present AskUserQuestion with categories as multi-select options
- Offer personal/sensitive PDFs separately (keep, move to Documents, or delete)
- Execute selected actions
Categorization Pattern
/usr/bin/env bash << 'DL_LIST_EOF'
echo "=== Downloads by date and size ==="
find "$HOME/Downloads" -maxdepth 1 \( -type f -o -type d \) ! -path "$HOME/Downloads" | \
while read -r f; do
mod_date=$(stat -f '%Sm' -t '%Y-%m-%d' "$f" 2>/dev/null)
size=$(du -sh "$f" 2>/dev/null | cut -f1)
echo "${mod_date} ${size} $(basename "$f")"
done | sort
DL_LIST_EOF
AskUserQuestion Template
When presenting Downloads cleanup options, use this pattern:
- Question 1 (multiSelect: true) - "Which items in ~/Downloads do you want to delete?"
- Group by type: movie files (with total size), old PDFs/docs, dev artifacts, app exports
- Question 2 (multiSelect: false) - "What about personal/sensitive PDFs?"
- Options: Keep all, Move to Documents, Delete (already have copies)
- Question 3 (multiSelect: false) - "Ongoing cleanup tool preference?"
- Options: dust + dua-cli, Hazel automation, custom launchd script
Disk Analysis Tools Reference
Comparison (Benchmarked on ~632GB home directory, Apple Silicon)
| Tool | Wall Time | CPU Usage | Interactive Delete | Install |
| ----------- | --------- | -------------------- | ------------------------ | ---------------------- |
| dust | 20.4s | 637% (parallel) | No (view only) | brew install dust |
| gdu-go | 28.8s | 845% (very parallel) | Yes (TUI) | brew install gdu |
| dua-cli | 37.1s | 237% (moderate) | Yes (staged safe delete) | brew install dua-cli |
| ncdu | 96.6s | 43% (single-thread) | Yes (TUI) | brew install ncdu |
Recommended Combo
dustfor quick "where is my space going?" - fastest scanner, tree outputdua iorgdu-gofor interactive exploration with deletion
Quick Usage
# dust - instant tree overview
dust -d 2 ~ # depth 2
dust -r ~/Library # reverse sort (smallest first)
# dua - interactive TUI with safe deletion
dua i ~ # navigate, mark, delete with confirmation
# gdu-go - ncdu-like TUI, fast on SSDs
gdu-go ~ # full TUI with delete support
gdu-go -n ~ # non-interactive (for scripting/benchmarks)
Install All Tools
brew install dust dua-cli gdu
Note: gdu installs as gdu-go to avoid conflict with coreutils.
Quick Wins Summary
Ordered by typical space reclaimed (highest first):
| Action | Typical Savings | Risk | Command |
| ------------------------------- | --------------- | -------------------------- | ----------------------------------- |
| uv cache clean | 5-15 GB | None (re-downloads) | uv cache clean --force |
| brew cleanup --prune=all | 3-10 GB | None (re-downloads) | brew cleanup --prune=all |
| Delete movie files in Downloads | 2-10 GB | Check first | Manual after AskUserQuestion |
| npm cache clean --force | 0.5-2 GB | None (re-downloads) | npm cache clean --force |
| pip cache purge | 0.5-2 GB | None (re-downloads) | pip cache purge |
| Prune old rustup toolchains | 2-5 GB | Keep current | rustup toolchain list then remove |
| Docker system prune | 5-30 GB | Removes stopped containers | docker system prune -a |
| Empty Trash | Variable | Irreversible | rm -rf ~/.Trash/* |
Post-Change Checklist
After modifying this skill:
- [ ] Cache commands tested on macOS (Apple Silicon)
- [ ] Benchmark data still current (re-run if tools updated)
- [ ] AskUserQuestion patterns match current tool API
- [ ] All bash blocks use
/usr/bin/env bash << 'EOF'wrapper - [ ] No hardcoded user paths (use
$HOME) - [ ] Append changes to evolution-log.md
Troubleshooting
| Issue | Cause | Solution |
| -------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| uv cache clean hangs | Lock held by running uv | Use --force flag |
| brew cleanup frees 0 bytes | Already clean or formulae linked | Run brew cleanup --prune=all |
| find reports permission denied | System Integrity Protection | Add 2>/dev/null to suppress |
| gdu command not found | Installed as gdu-go | Use gdu-go (coreutils conflict) |
| dust shows different size than df | Counting method differs | Normal - df includes filesystem overhead |
| Stale file scan is slow | Deep directory tree | Limit -maxdepth or exclude more paths |
| Docker not accessible | Desktop app not running | Start Docker.app or skip Docker cleanup |
| parse error near TASK_ID=$(pueue add ...) from heredoc with spaced paths | A user shell hook (e.g. pueue submission) re-parses the command string and breaks on ${var}/Path With Spaces/* globs inside heredocs | Write multi-line scripts to /tmp/<name>.sh first via Write tool, then invoke as bash /tmp/<name>.sh — bypasses the inline heredoc → hook re-quote path entirely |
Hook-safe multi-line scripts
If the user's shell environment has bash hooks that intercept tool calls (pueue, asciinema, etc.) and the heredoc pattern fails with cryptic parse errors, write the script to a temp file and invoke it:
# Instead of: bash << 'EOF' ... EOF
# Use: Write tool → /tmp/<task>.sh, then:
bash /tmp/<task>.sh
Single-line bash invocations like du -sh "$HOME/Library/Application Support"/Google/* 2>/dev/null | sort -rh | head work fine even with hooks installed — only multi-line heredocs containing spaced-path globs are problematic.
Post-Execution Reflection
After this skill completes, reflect before closing the task:
- Locate yourself. — Find this SKILL.md's canonical path before editing.
- What failed? — Fix the instruction that caused it.
- What worked better than expected? — Promote to recommended practice.
- What drifted? — Fix any script, reference, or dependency that no longer matches reality.
- Log it. — Evolution-log entry with trigger, fix, and evidence.
Do NOT defer. The next invocation inherits whatever you leave behind.