/agent lists subagents but no longer opens the interactive thread switcher

What version of Codex CLI is running?

codex-cli 0.144.6

What subscription do you have?

ChatGPT account (exact tier not relevant/confirmed for this TUI behavior).

Which model were you using?

GPT-5 family; this appears independent of model selection.

What platform is your computer?

Linux x86_64 (NixOS), kernel 7.1.3.

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

TUI running with TERM=xterm-256color, inside Zellij.

What issue are you seeing?

When subagents are active, entering /agent prints/lists the running subagents but does not open the interactive agent-thread switcher. There is no apparent way to select an agent and inspect its live thread.

This previously opened a switcher menu. The current Codex manual also says:

Use /agent in the CLI to switch between active agent threads and inspect the ongoing thread.

There does not appear to be a documented /agent <name> fallback syntax, so the regression removes the user's ability to inspect a running subagent from the CLI.

What steps can reproduce the bug?

1. Start an interactive Codex CLI session.
2. Ask the parent agent to spawn one or more subagents.
3. Run the parent thread under an active /goal continuation.
4. Wait until the subagents appear as active/running.
5. Enter /agent.
6. Observe that Codex lists the agent threads as text, but no interactive selection/switcher menu appears.
7. Attempting to select an agent is therefore not possible.

What is the expected behavior?

/agent should open the interactive switcher and allow selecting an active or completed agent thread, as documented and as prior versions did.

If the roster-only behavior is intentional, the CLI should expose and document another way to open a listed thread (for example, /agent <id-or-name>).

Additional information

A related closed issue, #16914, involved the TUI exiting during a subagent/thread switch when skills/list failed. This report is different: the TUI remains alive, but the switcher UI never appears.

The active subagents were created successfully and continued running; only navigation into their threads was unavailable.

The parent thread was pursuing an active /goal when this occurred. It is not yet known whether goal continuation is required to reproduce the problem, but it may be relevant to the TUI state transition.