[Windows][26.818.2872.0] Codex Desktop crashes during tool execution; app-server restarts and resumes thread #39964

Summary

Codex Desktop on Windows 11 repeatedly crashes during real coding/tool execution and shows the “ChatGPT stopped unexpectedly” recovery screen.

The failure is reproducible during project inspection / command execution. The same local project remains usable through Codex CLI on the same machine.

I inspected the local Codex log database read-only. In one captured failure, the active app-server process stopped appearing without a recorded fatal error, a new app-server process started ~37 seconds later, and the existing thread was successfully resumed with parse errors: 0.

After resume, the log also contains:

codex_features: unknown feature key in config: thread_tools

I do not know whether that warning is causal; I am including it because it appears in the recovery sequence and similar feature-version skew has been reported before.

Environment

• Platform: Windows 11 x64
• Codex Desktop package: OpenAI.Codex 26.818.2872.0
• Standalone Codex CLI: codex-cli 0.149.0
• CLI works on the same machine/project while Desktop crashes

Reproduction

1. Open Codex Desktop on Windows.
2. Open or resume a coding conversation for a local project.
3. Start a substantive coding task that requires project inspection and command/tool execution.
4. During active command/tool execution, Codex Desktop eventually terminates or shows “ChatGPT stopped unexpectedly.”
5. Restart/reopen Codex Desktop.
6. The previous conversation can be resumed.

Simple app usage is substantially more stable; the repeated crashes have occurred during real coding/tool execution.

Captured restart timeline

Timezone: -03:00

• Old app-server process: PID 1320
• Last observed normal activity from that process: approximately 2026-08-21 00:11:43 -03:00
• Immediately before disappearing it was still emitting normal events such as:

app-server event: item/commandExecution/outputDelta

• No fatal/error entry was captured immediately before that process disappeared.
• New app-server process: PID 14420
• New process startup: approximately 2026-08-21 00:12:20 -03:00
• The new process then performed thread/resume.
• Resume result:

Resumed rollout with 262 items ... parse errors: 0

• During the resumed initialization, the log contains:

codex_features: unknown feature key in config: thread_tools

There is also a PowerShell shell-snapshot warning:

Failed to create shell snapshot for powershell: Shell snapshot not supported yet for PowerShell

That warning appears benign and is included only for completeness.

Troubleshooting already performed

• Backed up ~/.codex before changes.
• Validated the old config.toml syntactically with Python tomllib (CONFIG TOML OK).
• Disabled the old config and let Codex Desktop regenerate a fresh config.
• Completed the Windows one-time permission/setup flow.
• Codex Desktop then launched normally.
• The crash later recurred during substantive coding/tool execution, so the original config does not appear to fully explain the issue.
• The recovered thread reports parse errors: 0, so the conversation history itself does not appear corrupted.
• The local project remains intact and usable through the standalone Codex CLI.

Feedback diagnostics

I submitted in-app feedback from the affected Desktop session with the current session logs included.

Feedback ID:

01a021e9-6309-7480-8115-591694279895

Expected behavior

A tool/command failure or app-server restart should be recoverable without terminating the Desktop app. If an unknown feature key is supplied, it should be ignored or handled gracefully rather than destabilizing the app-server.

Actual behavior

The app-server disappears during active work, a new process starts and successfully resumes the thread, but the Desktop experience is interrupted by the crash/recovery screen.

Possibly related issues

• [Windows][26.721.4979.0] app-server disconnect/recovery causes full desktop app termination under concurrent tasks #35782 — Windows app-server disconnect/recovery causing full Desktop termination under concurrent/high-load tasks. This looks behaviorally close, but my reproduction is on a much newer Desktop package (26.818.2872.0) and I did not capture the same EPIPE sequence.
• App-server crashes on any tool call ("thread_tools" unknown feature key) — sudden onset, no local trigger #29140 — app-server crashes on tool calls with unknown feature key in config: thread_tools. That issue was closed after reports that the problem appeared fixed in later builds, so this may represent a regression or a different Desktop manifestation.

I can provide additional sanitized excerpts from ~/.codex/logs_2.sqlite if maintainers need them. I am intentionally not attaching the full database/session transcript publicly because it may contain private project/session data.