Work fails to create projectless thread: `Projectless thread directory must be a real directory`

Bug description

When creating a new chat in ChatGPT Work, chat creation fails with the following error:

Projectless thread directory must be a real directory

This appears to be incorrect directory validation for a projectless Work thread.

A normal cloud-based Work chat that is not associated with a ChatGPT Project should not require a local filesystem directory. However, the current validation logic seems to require directory to point to an existing real directory whenever project is not set.

Error message

创建聊天时出错

Projectless thread directory must be a real directory

Steps to reproduce

1. Open ChatGPT Work.
2. Start a new Work chat without placing it inside a ChatGPT Project.
3. Attempt to create the chat.
4. Chat creation fails immediately.

Expected behavior

A projectless cloud Work thread should be created normally without requiring a local filesystem directory.

Conceptually:

Create Work thread
├─ Project thread → use project context
└─ Projectless cloud thread → create normally without local directory

A local directory should only be required when explicitly creating or opening a local-folder-based Work session.

Actual behavior

The projectless thread appears to be validated as though it were a local-folder thread:

project = null
directory = null / invalid
↓
directory validator runs
↓
Projectless thread directory must be a real directory
↓
thread creation fails

Possible cause

There may be an incorrect invariant or validation condition similar to:

if (!project) {
    assert(isRealDirectory(directory))
}

when the validation likely needs to distinguish between:

• project-backed cloud threads
• projectless cloud threads
• local-directory-backed threads

Directory validation should likely only run when a thread is explicitly configured to use a local directory.

Impact

This can completely prevent users from creating normal projectless Work chats.

It may also indicate that local Work thread validation and cloud Work thread validation are being conflated.

Environment

• Product: ChatGPT Work
• Platform: Web / desktop browser
• Date observed: 2026-08-16
• Error is reproducible when attempting to create a projectless Work thread

Screenshot / observed UI

The UI displays:

创建聊天时出错
Projectless thread directory must be a real directory

Suggested fix

Separate thread validation paths based on thread type rather than inferring local-directory requirements from the absence of a Project.

In particular, project == null should not itself imply that directory must exist.