Codex - OpenAI’s coding agent

[tkatska]

Type: Performance Issue

Title:
Codex VS Code extension crashes with unknown feature key: thread_tools

Description:
After upgrading Codex, the VS Code extension crashes immediately with:

codex_features: unknown feature key in config: thread_tools

I confirmed that thread_tools is not present in ~/.codex/config.toml.

Troubleshooting already completed:

• Fully restarted VS Code
• Uninstalled and reinstalled the Codex extension
• Tried both release and pre-release versions
• Renamed ~/.codex to ~/.codex-backup to create completely fresh local state
• Cleared Codex temporary/cache files
• Started a new thread

The issue still happens with a fresh ~/.codex directory, so it appears that thread_tools is being supplied outside my local config or there is an extension/runtime version mismatch.

Environment:

• macOS
• VS Code
• Codex IDE extension
• ChatGPT Plus

VS Code version: Code 1.125.1 (Universal) (fcf604774b9f2674b473065736ee75077e256353, 2026-06-19T08:39:34Z)
OS version: Darwin x64 24.6.0
Modes:

[microsoft-github-policy-service]

Team, please add a Type:Bug/Type:Feature/Type:CustomerSupport label as applicable.

[madhurivadaligithub]

Since this is extension-specific, please reach out to the extension owner through the Q&A for prompt response.

Regards,
VS Marketplace Team