Project config is not loaded when resuming a thread via /resume or codex resume #15007

What version of Codex CLI is running?

codex-cli 0.115.0

What subscription do you have?

no

Which model were you using?

gpt-5.4

What platform is your computer?

Microsoft Windows NT 10.0.26100.0 x64

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

No response

What issue are you seeing?

Summary

When I start Codex normally with codex inside a project directory, it correctly loads the project-level config (Project config).

However, if I resume a thread either by:

• using /resume inside Codex, or
• starting with codex resume ...

Codex does not load the project-level config. It falls back to the system-level config (System config) instead.

Why this matters

In my setup:

• System config uses my official OpenAI account/settings
• Project config overrides that and uses a third-party model endpoint for this specific project

Because resumed sessions ignore the project config, requests are sent to the wrong endpoint/account after resume.

What steps can reproduce the bug?

Steps to reproduce

1. Configure System config to use the default/official OpenAI endpoint/account.
2. Configure Project config in a project directory to use a different provider or third-party model endpoint.
3. cd into that project directory.
4. Run codex.
5. Confirm that Codex correctly uses the project-level config and sends requests to the third-party endpoint.
6. Create a conversation/thread, then resume it in either of these ways:
   • use /resume inside Codex
   • or run codex resume <thread-id> from the same project directory
7. Observe that Codex no longer uses the project-level config, and instead uses the system-level config.

What is the expected behavior?

Expected behavior

When resuming a thread from within a project directory, Codex should still load and apply the project-level config exactly like a normal
In other words, resume should preserve the same config resolution behavior as a fresh start in that project.

Additional information

Environment

• OS: Windows
• Codex CLI version: codex-cli 0.115.0
• Resume method tested:
  • /resume
  • codex resume <thread-id>

Additional notes

This seems specifically related to config resolution during resume flow.

A fresh codex launch inside the same project directory works correctly, so the project config itself is valid and can be loaded normally.

Suspected cause

It looks like the resume flow may not be resolving the current project directory and/or loading project-level config before restoring the thread.