Codex CLI 0.143.0: all workspace tools fail with "unsupported call: exec_command" on Linux

What version of Codex CLI is running?

codex-cli 0.143.0

What subscription do you have?

pro

Which model were you using?

5.5

What platform is your computer?

• Ubuntu 24.04, Linux x86_64

What terminal emulator and version are you using (if applicable)?

_No response_

Codex doctor report

What issue are you seeing?

Codex version

codex-cli 0.143.0

Environment

• Ubuntu 24.04, Linux x86_64
• Installation: official standalone installer
• Authentication: ChatGPT
• Workspace: Git repository under /var/www/...
• Shell: /bin/bash
• Previous working version: 0.142.5

Problem

Immediately after updating from 0.142.5 to 0.143.0, all workspace command execution failed before reaching the sandbox.

Even a minimal request such as running pwd failed with:

unsupported call: exec_command

Starting a new thread, restarting Codex, and restarting the CLI did not resolve the problem.

Diagnostics

codex doctor on 0.143.0 reported:

• 17 ok
• 0 warnings
• 0 failures
• Config loaded successfully
• Authentication configured
• WebSocket connected
• Git repository detected
• Sandbox helpers present
• State databases healthy

The update to 0.143.0 occurred on 2026-07-09 at approximately 05:34 UTC.

Reproduction

1. Run Codex CLI 0.143.0 on Linux.
2. Open an existing Git workspace.
3. Ask Codex to execute pwd.
4. The tool invocation fails with unsupported call: exec_command.

Version comparison

Running the cached 0.142.5 binary directly in the same environment, with the same account, repository, shell, and server:

/root/.codex/packages/standalone/releases/0.142.5-x86_64-unknown-linux-musl/bin/codex

Then requesting pwd immediately succeeds and returns the correct workspace path.

Switching the current symlink back to 0.142.5 restores workspace tool execution.

Additional rollback issue

Version 0.143.0 wrote this configuration section:

[tui.model_availability_nux]

Its boolean values cannot be parsed by 0.142.5, which reports:

invalid type: boolean false, expected u32

Removing that nonessential section allowed 0.142.5 to start normally.

Workaround

• Roll back to 0.142.5.
• Set check_for_update_on_startup = false.

Expected behavior

exec_command and other workspace tools should remain callable after upgrading to 0.143.0.

What steps can reproduce the bug?

see above

What is the expected behavior?

_No response_

Additional information

_No response_