How do I install the Seatbelt skill?

Run npx skillmds@latest add tomevault-io/seatbelt in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Seatbelt safe to use?

This skill has not completed SkillMD's automated safety review yet. Independent scanners report: SkillSpector: PASS, Skill Scanner: WARNING. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Seatbelt?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Seatbelt free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Seatbelt?

tomevault-io (@tomevault-io) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Seatbelt by tomevault-io — Agent Skill

Name: Seatbelt
Author: tomevault-io

File contents

Seatbelt Skill

macOS sandbox configuration using Seatbelt (sandbox-exec).

Commands

Command	Description
`seatbelt_profile`	Generate Seatbelt profile
`seatbelt_export`	Export SBPL profile to file

Quick Usage

# Generate profile with override
nickel export examples/python-script-runner.ncl --field _profile -f text -- \
  --override "home_dir=\"$HOME\"" \
  --override "script_path=\"$HOME/projects/my_script.py\"" \
  > /tmp/profile.sb

# Run in sandbox
sandbox-exec -f /tmp/profile.sb /usr/bin/python3 "$HOME/projects/my_script.py"

Nickel CLI

Basic Export

# Export as text
nickel export config.ncl -f text

# Export specific field
nickel export --field _profile config.ncl -f text

Customize Mode

# List available fields
nickel export config.ncl -- list

# Override values
nickel export config.ncl -f text -- \
  --override "home_dir=\"$HOME\"" \
  --override "script_path=\"$HOME/projects/my_script.py\""

Concepts

Topic	Description	Reference
Profile Types	Sandbox profiles	profiles.md
SBPL Syntax	SBPL reference	sbpl-syntax.md
Path Matching	Path patterns	path-matching.md

Python Sandbox Example

# Generate profile
nickel export examples/python-script-runner.ncl --field _profile -f text -- \
  --override "home_dir=\"$HOME\"" \
  --override "script_path=\"$HOME/projects/my_script.py\"" \
  --override 'python_path="/usr/bin/python3"' \
  > /tmp/profile.sb

# Run
sandbox-exec -f /tmp/profile.sb /usr/bin/python3 "$HOME/projects/my_script.py"

Best Practices

Use --override to customize paths per user
Use --field _profile to export only the profile
Use -f text for sandbox-exec (not JSON)
Test profiles with sandbox-exec before deployment

Related Skills

Topic	Description	Reference
Nsjail	Linux sandboxing	nsjail

Converted and distributed by TomeVault — claim your Tome and manage your conversions.

---name: seatbeltdescription: Use when configuring macOS sandbox execution with Seatbelt profiles, generating sandbox-exec profiles, or testing macOS sandbox restrictions.---# Seatbelt SkillmacOS sandbox configuration using Seatbelt (sandbox-exec).## Commands| Command | Description ||---------|-------------|| [`seatbelt_profile`](#seatbelt_profile) | Generate Seatbelt profile || [`seatbelt_export`](#seatbelt_export) | Export SBPL profile to file |## Quick Usage```bash# Generate profile with overridenickel export examples/python-script-runner.ncl --field _profile -f text -- \ --override "home_dir=\"$HOME\"" \ --override "script_path=\"$HOME/projects/my_script.py\"" \ > /tmp/profile.sb# Run in sandboxsandbox-exec -f /tmp/profile.sb /usr/bin/python3 "$HOME/projects/my_script.py"```## Nickel CLI### Basic Export```bash# Export as textnickel export config.ncl -f text# Export specific fieldnickel export --field _profile config.ncl -f text```### Customize Mode```bash# List available fieldsnickel export config.ncl -- list# Override valuesnickel export config.ncl -f text -- \ --override "home_dir=\"$HOME\"" \ --override "script_path=\"$HOME/projects/my_script.py\""```## Concepts| Topic | Description | Reference ||-------|-------------|-----------|| Profile Types | Sandbox profiles | [profiles.md](references/profiles.md) || SBPL Syntax | SBPL reference | [sbpl-syntax.md](references/sbpl-syntax.md) || Path Matching | Path patterns | [path-matching.md](references/path-matching.md) |## Python Sandbox Example```bash# Generate profilenickel export examples/python-script-runner.ncl --field _profile -f text -- \ --override "home_dir=\"$HOME\"" \ --override "script_path=\"$HOME/projects/my_script.py\"" \ --override 'python_path="/usr/bin/python3"' \ > /tmp/profile.sb# Runsandbox-exec -f /tmp/profile.sb /usr/bin/python3 "$HOME/projects/my_script.py"```## Best Practices- Use `--override` to customize paths per user- Use `--field _profile` to export only the profile- Use `-f text` for sandbox-exec (not JSON)- Test profiles with `sandbox-exec` before deployment## Related Skills| Topic | Description | Reference ||-------|-------------|-----------|| Nsjail | Linux sandboxing | [nsjail](../nsjail/SKILL.md) |---> Converted and distributed by [TomeVault](https://tomevault.io/claim/tao3k) — claim your Tome and manage your conversions.

Frequently asked questions

Seatbelt