Osx Tuning

What it does

When your agent uses it

• The user asks to tune macOS
• Raise file descriptor limits
• Optimize for Docker/Go/VM performance
• Increase maxfiles/maxproc/somaxconn

Example prompts

• “tune macOS”
• “raise file descriptor limits”
• “fix ulimit”
• “/osx-tuning”

Requirements

• Docker

Workflow steps

3 steps, taken from the step headings in SKILL.md.

1. 1launchd maxfiles (system-wide)
2. 2Per-shell ulimit (interactive shells)
3. 3Boot-time sysctls

What it can do on your machine

Read from SKILL.md and the folder at commit c4c83e6. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are bash and xml).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Hosts in commands or code, which the agent is likely to contact:

  • apple.com

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Osx Tuning loads about 1.6k tokens when it runs. Until then it costs about 137 tokens; SKILL.md has 475 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~137

When it runs · the whole SKILL.md, loaded when a task matches

~1.6k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NoteRuns commands with sudoSKILL.md:67

  sudo cp /tmp/limit.maxfiles.plist /Library/LaunchDaemons/limit.maxfiles.plist

• NoteRuns commands with sudoSKILL.md:68

  sudo chown root:wheel /Library/LaunchDaemons/limit.maxfiles.plist

• NoteRuns commands with sudoSKILL.md:69

  sudo chmod 644 /Library/LaunchDaemons/limit.maxfiles.plist

• NoteRuns commands with sudoSKILL.md:70

  sudo launchctl load -w /Library/LaunchDaemons/limit.maxfiles.plist

• NoteRuns commands with sudoSKILL.md:140

  sudo launchctl list | grep -iE "sysctl|maxfiles"   # both loaded, exit 0

• NoteRuns commands with sudoSKILL.md:146

  sudo launchctl unload -w /Library/LaunchDaemons/limit.maxfiles.plist

• NoteRuns commands with sudoSKILL.md:147

  sudo rm /Library/LaunchDaemons/limit.maxfiles.plist

• NoteRuns commands with sudoSKILL.md:148

  sudo launchctl unload -w /Library/LaunchDaemons/com.local.sysctl.plist

• NoteRuns commands with sudoSKILL.md:149

  sudo rm /Library/LaunchDaemons/com.local.sysctl.plist

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from dimetron/pi-go at commit c4c83e6, republished under its MIT licence (© dimetron). 475 words, ~1,633 tokens.

name

osx-tuning

description

Tune macOS resource limits and sysctls for best performance with Go development, Docker/OrbStack, and Linux VMs. Use this skill whenever the user asks to "tune macOS", "raise file descriptor limits", "fix ulimit", "optimize for Docker/Go/VM performance", "increase maxfiles/maxproc/somaxconn", or reports EMFILE/too-many-open-files, connection refused under load, or slow container/VM networking. Covers the full chain: launchd maxfiles, per-shell ulimit, and boot-time sysctl tuning via LaunchDaemons, with verification and revert steps.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
  <dict>
    <key>Label</key>
    <string>limit.maxfiles</string>
    <key>ProgramArguments</key>
    <array>
      <string>launchctl</string>
      <string>limit</string>
      <string>maxfiles</string>
      <string>65536</string>
      <string>unlimited</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>ServiceIPC</key>
    <false/>
  </dict>
</plist>

sudo cp /tmp/limit.maxfiles.plist /Library/LaunchDaemons/limit.maxfiles.plist
sudo chown root:wheel /Library/LaunchDaemons/limit.maxfiles.plist
sudo chmod 644 /Library/LaunchDaemons/limit.maxfiles.plist
sudo launchctl load -w /Library/LaunchDaemons/limit.maxfiles.plist

launchctl limit maxfiles   # expect: maxfiles 65536 unlimited

# Raise open file descriptor soft limit (hard limit is unlimited)
ulimit -n 65536

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
  <dict>
    <key>Label</key>
    <string>com.local.sysctl</string>
    <key>ProgramArguments</key>
    <array>
      <string>/bin/sh</string>
      <string>-c</string>
      <string>sysctl -w kern.maxprocperuid=4000 kern.ipc.somaxconn=1024 net.inet.tcp.sendspace=262144 net.inet.tcp.recvspace=262144 net.inet.tcp.win_scale_factor=5 net.inet.tcp.mssdflt=1460</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>ServiceIPC</key>
    <false/>
  </dict>
</plist>

launchctl limit maxfiles          # maxfiles 65536 unlimited
ulimit -n                          # 65536 in a new shell
sysctl kern.maxprocperuid kern.ipc.somaxconn \
       net.inet.tcp.sendspace net.inet.tcp.recvspace \
       net.inet.tcp.win_scale_factor net.inet.tcp.mssdflt
sudo launchctl list | grep -iE "sysctl|maxfiles"   # both loaded, exit 0

sudo launchctl unload -w /Library/LaunchDaemons/limit.maxfiles.plist
sudo rm /Library/LaunchDaemons/limit.maxfiles.plist
sudo launchctl unload -w /Library/LaunchDaemons/com.local.sysctl.plist
sudo rm /Library/LaunchDaemons/com.local.sysctl.plist
# remove the ulimit line from ~/.zshrc

© dimetron, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in internal/extension/bundled_skills/osx-tuning of dimetron/pi-go.

Open the folder on GitHubat commit c4c83e6