Built-in Playwright skill fails in Codex desktop sandbox with listen EPERM during browser startup

Summary

The built-in playwright skill does not work reliably in Codex desktop's default sandboxed environment.

In this environment, Playwright CLI/MCP browser startup fails with listen EPERM: operation not permitted, which prevents opening a browser session without escalating out of the sandbox.

Given that this is an OpenAI-provided skill, the expectation is that it should work in the default Codex environment without requiring unsandboxed approval.

Environment

• Codex desktop
• macOS
• sandboxed execution enabled
• using the built-in playwright skill and its wrapper script: ~/.codex/skills/playwright/scripts/playwright_cli.sh

Repro

1. Confirm npx is available.
2. Use the provided Playwright skill wrapper or the cached Playwright CLI directly.
3. Redirect Playwright state into the workspace so filesystem permissions are not the issue:

• PLAYWRIGHT_DAEMON_SESSION_DIR=$PWD/tmp/playwright/daemon
• PLAYWRIGHT_MCP_OUTPUT_DIR=$PWD/tmp/playwright/output
• PLAYWRIGHT_MCP_USER_DATA_DIR=$PWD/tmp/playwright/user-data

1. Run a browser-starting command such as playwright-cli open http://localhost:3000.

Actual Result

Browser startup fails with a local socket bind error such as:

listen EPERM: operation not permitted 0.0.0.0

I also reproduced the same class of failure with plain Node inside the sandbox:

const net = require("net");
const server = net.createServer();
server.listen(0);

That fails with EPERM.

Binding explicitly to localhost also fails:

server.listen(0, "127.0.0.1");

So this is not just a 0.0.0.0 default-host issue; the sandbox appears to block local listening sockets entirely.

Expected Result

The built-in playwright skill should work in Codex desktop's default sandbox, or Codex should provide a supported sandbox-safe transport for Playwright browser startup.

Notes

• Moving Playwright session/cache/output paths into the workspace fixed file-permission problems, but not browser startup.
• The remaining blocker appears to be that Playwright CLI/MCP requires a local listen() during launch, and Codex desktop sandbox disallows it.
• Chromium specifically appears to hit a path that allocates a local CDP port during launch, but even plain local net.createServer().listen(...) is blocked in this sandbox.

Impact

This makes the built-in playwright skill effectively unusable in the default sandboxed Codex desktop environment, forcing repeated unsandboxed approvals for a first-party workflow.

Related

• openai/codex#2508
• microsoft/playwright#36412