Regression: Computer Use tool-host missing in Windows app 26.707.12708 / CLI 0.144.5

Start with the bundled scripts/computer-use-client.mjs and the CLI/App boundary that publishes tools to a new task; compare the toolset and transcript behavior between CLI 0.144.0-alpha.4 and 0.144.5. Done means a fresh Windows task exposes the execution tool required by the Computer Use skill and can perform the documented read-only bootstrap and app-state inspection.

Computer Use tool-host is not exposed in Codex App 26.707.12708 / CLI 0.144.5

Component

• Codex Windows desktop app: 26.707.12708.0
• Bundled Codex CLI: 0.144.5
• Bundled Computer Use plugin: 26.707.91948
• OS: Windows 11 Professional, build 26200

Summary

New Codex tasks no longer receive the callable tool-host required by the
bundled Computer Use skill. The skill is discovered and its runtime starts, but
the execution tool described by the skill (mcp__node_repl__js, previously
reached through the code tool-host) is absent from the task toolset.

This worked in a prior session using Codex CLI 0.144.0-alpha.4, where the
session transcript contains real custom_tool_call events for exec and
successful mcp_tool_call_end events for the node_repl server. That session
successfully read the accessibility state of Claude Desktop.

In fresh sessions using CLI 0.144.5, the string mcp__node_repl__js appears
only in the injected Computer Use skill instructions; no callable tool with
that ID is published and no actual tool call can be made.

Steps to reproduce

1. Install/start Codex for Windows 26.707.12708.0.
2. Enable Computer Use for applications in Codex settings.
3. Confirm the bundled Computer Use plugin is enabled.
4. Start a completely new task after restarting Codex.
5. Ask the agent to perform a passive Computer Use check, for example:
   list open applications and read the state of Claude Desktop without clicks,
   typing, messages, or model calls.
6. Observe that the Computer Use skill is available, but the task has no
   callable Computer Use execution interface.

Expected result

The new task exposes the execution tool required by the bundled Computer Use
skill, allowing the documented bootstrap through
scripts/computer-use-client.mjs and then read-only list_apps / app-state
inspection.

Actual result

The skill is listed and readable, but the execution tool is absent. The agent
cannot run the documented bootstrap and must report that Computer Use cannot be
called.

Diagnostics already performed

• Verified that
  scripts/computer-use-client.mjs exists in the bundled plugin.
• Verified that the bundled plugin cache matches the plugin shipped with the
  installed Codex app.
• Verified that the local Computer Use runtime processes start.
• Verified that computer_use = true, code_mode_host = true, and
  code_mode = true do not restore publication of the tool.
• Confirmed that the legacy js_repl feature is marked removed; it was not used
  as a workaround.
• Restarted Codex and reproduced in a newly created task.
• Repaired an unrelated WindowsApps PowerShell alias problem by installing
  PowerShell 7.6.3 MSI at C:\Program Files\PowerShell\7\pwsh.exe; direct
  PowerShell execution now works, but Computer Use remains unavailable.
• The failure occurs before screenshot capture or application interaction, so
  it is not a Windows Graphics Capture error.

Regression evidence

• Working session: CLI 0.144.0-alpha.4
  • real custom_tool_call name=exec
  • successful mcp_tool_call_end for node_repl
  • successful read-only accessibility inspection of Claude Desktop
• Failing sessions: CLI 0.144.5
  • no exec code tool-host in the task toolset
  • no callable mcp__node_repl__js
  • reproduced after restart in a fresh task

Impact

Computer Use is effectively unavailable even though the bundled plugin,
settings, runtime, and skill are present. This blocks Windows application
automation and also prevents delegating a narrow desktop-control subtask while
keeping the main task on another model.

Privacy

No authentication tokens, cookies, private chat contents, or auth-cache
contents are included in this report.