Explicit create_thread titles are shortened while set_thread_title preserves the same text

What version of the Codex App are you using (From About Codex dialog)?

26.901.2854.0, verified from the installed Windows package.

What subscription do you have?

ChatGPT account with Codex access; subscription tier is not material to this reproduction.

What platform is your computer?

Microsoft Windows NT 10.0.26220.0, x64.

What issue are you seeing?

An explicitly supplied create_thread title is shortened as if it were an automatically generated title. A subsequent set_thread_title call accepts and preserves exactly the same full text.

Requested title:
Visibility test agent created task with explicit full title

Title returned by direct read after creation:
Visibility test agent created task with…

After set_thread_title, direct read and the pinned-task listing both returned the complete requested title. This is stored/read-back text shortening, not only sidebar layout ellipsis.

What steps can reproduce the bug?

1. From an existing app task, call create_thread with a saved Git project, environment type worktree, the explicit title above, and a harmless prompt such as Do not use tools or edit files. Reply only: Visibility test ready.
2. Allow setup and the opening turn to complete; resolve the real thread ID.
3. Read the task by ID and compare its title with the requested string.
4. Call set_thread_title for that same ID with the original full title.
5. Read again and compare exact equality. If needed for discovery, pin the task and read its pinned inventory entry.

The same creation shortening and successful full-title restoration were also observed for two subsequent persistent role tasks with longer explicit titles.

What is the expected behavior?

Preserve explicitly supplied titles, consistent with set_thread_title. Apply automatic-title shortening to generated titles, or expose a deliberate title-length policy consistently across creation and rename.

The tool currently describes creation titles as normalized like generated titles; this report concerns that behavior's usability and inconsistency, rather than claiming it violates the current tool description.

Additional information

No installed binaries or state/history files were modified. The separate hidden-task issue is tracked in #32614; pinning was used only to inspect discovery. Phone and restart behavior were not tested. Private task IDs, paths and project content are omitted.

Start at the create_thread and set_thread_title entry points and reproduce the reported comparison using an explicit title. Trace where creation titles are normalized or shortened, then verify that an explicitly supplied title is preserved exactly while generated titles retain their intended behavior. Done means direct reads and pinned-task listings return the full requested title immediately after creation.