Inside OpenAI Codex

A thread you can test

Sandbox

5 notes move from the word to a real choice at work — understand it first, then decide whether to use it.

READING THREADOPEN
5notes
HOW TO READStart where you are stuck, then follow the evidence and trade-offs

Each note stands alone, or becomes the next step in this thread.

Inside OpenAI CodexNo login

THE QUESTION THIS PAGE ANSWERS

ANSWER FIRST

What is Sandbox, and which AI decisions does it change?

What shell the same command gets on three platforms. Wanting a sandbox and having a backend are two different questions This page keeps the related concepts, common mistakes, and practical notes in one reading thread.

DECISION RULE

First decide whether you are blocked by a definition, a choice, or verification; then choose the closest of the 5 notes below.

TRY NEXT

Start with “Sandbox manager: compile a permission profile into one command,” then restate the conclusion using your own task.

WATCH FOR

Do not treat every method in a topic as interchangeable. The answer changes with the input, risk, and acceptance bar.

THIS QUESTION THREAD

Put the word back inside the choice it changes.

5 notes
Sandbox

Sandbox manager: compile a permission profile into one command

What shell the same command gets on three platforms. Wanting a sandbox and having a backend are two different questions

Inside OpenAI Codex 9 min →
Sandbox

macOS: stitch a security policy into one string

On macOS, Seatbelt’s policy is stitched from text fragments. Paths go in a param table; a carve-out must block the node, its descendants, and a move

Inside OpenAI Codex 10 min →
Sandbox

Linux: build the view, then seccomp, then exec

On Linux, Codex first swaps the filesystem view with bubblewrap, then applies seccomp in the same helper, and only then execs the user command. Send one access request through and see which layer stops it

Inside OpenAI Codex 11 min →
Sandbox

Windows: restricted token, firewall filter, and two dedicated system users

Windows has no seatbelt and no bubblewrap. Codex stacks a restricted token, a firewall filter, and two dedicated system users into a sandbox — and why AppContainer does not fit this permission model

Inside OpenAI Codex 12 min →
Policy

execpolicy: Let the Policy File Carry Its Own Tests

Codex writes positive and negative examples into the rule itself: how a command is split, prefix-matched, and judged at the strictest level, and how load-time tests pin down false hits

Inside OpenAI Codex 10 min →