codex-sandbox

Create per-task Git sandboxes with isolated branches for Codex sessions.

131|13|Updated Dec 29, 2025
One-click install
npx skills add https://github.com/regenrek/agent-skills --skill codex-sandbox
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: codex-sandbox
Source: https://github.com/regenrek/agent-skills/tree/main/skills/codex-sandbox
Command: npx skills add https://github.com/regenrek/agent-skills --skill codex-sandbox

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

Codex sandboxing solves the problem of cross-task contamination and Git worktree friction by giving every task its own sandbox directory and isolated branch, ensuring predictable environments and safe isolation for Codex sessions.

Core Features & Use Cases

  • Create a dedicated sandbox per task, with a per-task branch and a safe upstream to the real remote.
  • Install safety hooks that prevent commits or pushes on main/master to reduce the risk of accidental changes to protected branches.
  • Use when running multiple Codex sessions or parallel tasks to avoid cwd/branch mixups and environment collisions.
  • Works across repo-scoped and user-scoped setups, with a minimal Python CLI and wrapping Bash helper.

Quick Start

Ask the agent to create a sandbox for a task using the codex_sandbox tool.

Frequently Asked Questions about codex-sandbox

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I isolate parallel Codex tasks to prevent Git worktree collisions?▼

Isolate parallel Codex tasks by creating a dedicated sandbox directory per task, cloning from a bare mirror and assigning each task its own separate branch to prevent Git worktree collisions and ensure predictable environments.

Can I block commits or pushes to main and master branches during Codex automation?▼

Block commits or pushes to main and master branches during Codex automation by installing safety hooks that prevent accidental changes to protected branches within each per-task sandbox environment.

How do I create a per-task sandbox for a Codex session?▼

Create a per-task sandbox for a Codex session by asking the agent to use the codex_sandbox tool, which parses remote URLs, manages bare mirrors, creates isolated sandboxes, and records metadata for full auditability.

Does Codex sandboxing work with both repo-scoped and user-scoped development workflows?▼

Codex sandboxing works with both repo-scoped and user-scoped development workflows, providing a minimal Python CLI and wrapping Bash helper to manage per-task sandboxes across different project configurations.

Why do I need a separate branch per task when running multiple Codex sessions?▼

You need a separate branch per task when running multiple Codex sessions to avoid cwd and branch mixups, prevent cross-task contamination, and ensure safe isolation between parallel Codex tasks.

What are the limitations of using bare mirrors for Git sandbox isolation?▼

A limitation of using bare mirrors for Git sandbox isolation is that the setup requires parsing remote URLs and managing the mirror cloning process, which may add overhead to multi-task projects compared to working directly in a single repository.