codexfast - enable Fast mode, GPT-5.5, and Plugins in OpenAI Codex.app

中文说明

A macOS patch script for OpenAI Codex.app that re-enables hidden custom API features on verified compatible builds.

codexfast is a single-file OpenAI Codex.app patcher for custom API users on macOS. It restores hidden Fast mode features such as the Settings Fast control, the composer /fast slash command, the composer Speed menu, GPT-5.5 model-list compatibility where needed, and Plugins access.

• Fast settings control in Settings
• Composer /fast slash command
• Speed submenu in the composer
• GPT-5.5 model-list compatibility for custom-API users where the supported build still needs it
• Plugins access for custom-API users

npx codexfast

Verified for Codex.app 26.506.31421 (build 2620), 26.506.21252 (build 2575), 26.429.61741 (build 2429), 26.429.30905 (build 2345), 26.429.20946 (build 2312), 26.422.71525 (build 2210), 26.422.62136 (builds 2180, 2176), 26.422.30944 (build 2080), 26.422.21637 (build 2056), 26.417.41555 (build 1858), and 26.415.40636 (build 1799). Feature scope: docs/feature-scope.md.

What It Does

Menu actions on the installed app:

1. View current status — detect version, target files, and whether patching is safe
2. Enable custom API features — restore the feature set above
3. Restore original state — roll back to the vendor bundle
4. Install auto-repair watcher — re-apply after a supported Codex update replaces app.asar
5. Uninstall auto-repair watcher — remove the launchd watcher

Patching unpacks app.asar, rewrites the frontend assets, repacks, updates the ElectronAsarIntegrity hash in Info.plist, and ad-hoc re-signs so Codex.app still launches.

How It Works

Codex.app already contains the Fast, /fast, Speed, model-list, and Plugins UI paths in its packaged frontend bundle, but some of those paths are hidden or disabled for custom API users by local gate checks. codexfast does not add a new backend service or call a private OpenAI API. It only changes the installed app bundle on verified builds.

The patcher reads the installed app version and build from Info.plist, then allows apply only when that exact version/build is in the strict compatibility whitelist. For a supported build, it unpacks Contents/Resources/app.asar into a temporary directory, searches webview/assets/*.js for stable feature needles, and applies narrow code-signature replacements that remove the custom-API gates or force the local UI availability flag on.

The unpack/repack step is required because Codex ships its renderer code inside the packed Electron archive app.asar; patching loose files under Contents/Resources/app would leave the app in a non-standard layout and can conflict with future updates. codexfast works in a temporary extraction directory and replaces only the packed app.asar archive.

Before replacing the archive, it keeps recovery paths: an archive backup at app.asar1 plus file-level *.codexfast.bak backups inside the repacked bundle. After repacking, it updates Electron's ASAR integrity hash in Info.plist. Because changing app.asar invalidates the app's original code signature, it then performs a local ad-hoc codesign so macOS can launch the modified app. This local signature passes codesign verification, but it replaces the vendor notarization, so macOS privacy permissions such as screen recording may need to be granted again. Restore reverses this by preferring the archive backup, then file backups, then inline restore rules.

Usage

macOS only. Requires Codex.app at /Applications, Node.js >=18.12.0, npm, and the built-in codesign.

Run the patcher:

npx codexfast

Or from a clone of this repo:

./bin/codexfast

Print help or the installed package version:

npx codexfast help
npx codexfast version

The script opens an interactive menu:

1) View current status
2) Enable custom API features
3) Restore original state
4) Install auto-repair watcher
5) Uninstall auto-repair watcher
q) Quit

The same actions are also available as non-interactive commands: status, apply, restore, install-watcher, and uninstall-watcher.

Command Reference

Command	Purpose
npx codexfast status	Inspect the installed Codex.app, print the detected version/build, compatibility state, and target patch status without changing the app.
npx codexfast apply	Apply the supported patch set to a compatible build, create backups, refresh Electron ASAR integrity, ad-hoc re-sign, and reset the screen-recording permission record.
npx codexfast restore	Remove the auto-repair watcher if installed, restore the vendor bundle from backup or inline restore rules, re-sign if needed, and reset the screen-recording permission record after a successful restore.
npx codexfast install-watcher	Install the per-user macOS launchd auto-repair watcher that monitors app.asar and runs the latest published repair after supported Codex updates.
npx codexfast uninstall-watcher	Remove the auto-repair watcher plist and local watcher runtime. This cleanup command does not require a healthy Codex.app installation.

View Status

Choose 1) View current status before changing anything. Status checks the installed Codex.app, reports the detected version/build, shows whether the build is supported, and lists the patch targets found in the app bundle.

Use this after every Codex update. If compatibility is not supported, do not enable the patch on that build.

Enable Features

Choose 2) Enable custom API features when status reports a supported build. This enables the supported feature set:

• Fast control in Settings
• /fast slash command in the composer
• Speed menu in the composer
• GPT-5.5 in the model list where the supported build still needs the compatibility patch
• Plugins access for custom-API users

The first enable run creates backups, updates app.asar, refreshes the Electron ASAR integrity hash, and runs an ad-hoc re-sign. Because re-signing changes the app identity used by macOS privacy checks, apply resets the Codex.app screen-recording permission record. Restart Codex.app after the script finishes and allow Screen & System Audio Recording when macOS asks.

Disable or Restore

Choose 3) Restore original state to turn the patch off. Restore first removes the auto-repair watcher if it is installed, then rolls Codex.app back to the vendor bundle when the archive backup is available and re-signs if needed. After a successful restore re-sign, the script also resets the Codex.app screen-recording permission record so macOS asks for a fresh decision on next launch.

Use restore before troubleshooting, before testing a fresh Codex update, or whenever you want to return to the original app behavior. If you want auto-repair again after restoring, reinstall the watcher explicitly.

Auto-Repair Watcher

Choose 4) Install auto-repair watcher or run:

npx codexfast install-watcher

This installs a per-user macOS launchd agent at ~/Library/LaunchAgents/com.codexfast.watcher.plist. The agent watches /Applications/Codex.app/Contents/Resources/app.asar and runs npx --yes codexfast@latest repair when Codex replaces the archive during an app update.

The watcher only applies changes when the newly installed version/build is already in the strict compatibility whitelist. Unsupported builds are skipped quietly and leave the app untouched.

repair is idempotent. If Codex is already patched, it reports that no changes were needed and leaves app.asar, Info.plist, and the app signature untouched, so the watcher does not loop on its own repair writes. If Codex is already running when the on-disk archive is repaired, fully quit and reopen Codex to load the patched frontend bundle.

To remove the watcher:

npx codexfast uninstall-watcher

Compatibility

The script does not use an official API — it matches code signatures in frontend build output, so it can break after a Codex update.

• Verified on Codex.app 26.506.31421 (build 2620)
• Verified on Codex.app 26.506.21252 (build 2575)
• Verified on Codex.app 26.429.61741 (build 2429)
• Verified on Codex.app 26.429.30905 (build 2345)
• Verified on Codex.app 26.429.20946 (build 2312)
• Verified on Codex.app 26.422.71525 (build 2210)
• Verified on Codex.app 26.422.62136 (builds 2180, 2176)
• Verified on Codex.app 26.422.30944 (build 2080)
• Verified on Codex.app 26.422.21637 (build 2056)
• Verified on Codex.app 26.417.41555 (build 1858)
• Verified on Codex.app 26.415.40636 (build 1799)
• Enable is blocked unless the installed version/build is whitelisted
• Auto-repair also skips unsupported version/build pairs quietly and does not modify the app
• View status and Restore work on any version
• The GPT-5.5 model-list patch only injects the UI catalog entry on supported builds that still need it. Codex.app 26.422.30944 and later builds are expected to expose GPT-5.5 through the official app path, so codexfast skips that apply target from 26.422.30944 onward. Your configured provider must still support gpt-5.5
• For Plugins, the script removes the custom-API gates needed to open the Plugins sidebar/page path on supported builds. On 26.429.20946, 26.429.30905, 26.429.61741, 26.506.21252, and 26.506.31421, it also removes the aggregate connector-unavailable install block and keeps install-modal plugin details visible. Actual plugin behavior can still depend on plugin state, connector runtime behavior, or admin restrictions

Re-run View current status after every Codex update.

Backup and Restore

First apply creates two backups:

• app.asar1 — archive-level backup of the original bundle
• *.codexfast.bak — file-level fallback. Restore also recognizes the legacy *.speed-setting.bak suffix from earlier releases.

Restore removes the auto-repair watcher before changing app.asar, then prefers app.asar1, falls back to .bak, then inline restoration. A future Codex auto-update may overwrite the patched state.

The local ad-hoc re-sign passes codesign integrity checks but replaces the vendor notarization. spctl --assess returning rejected is expected — use codesign --verify --deep --strict --verbose=2 /Applications/Codex.app to verify instead.

Troubleshooting

Script fails immediately — check /Applications/Codex.app exists, plus node -v reports 18.12.0 or later, npm -v, and codesign -h.

Re-sign step fails (macOS refused write) — run manually:

codesign --force --deep --sign - /Applications/Codex.app

macOS keeps asking to record this computer's screen and audio — apply and restore reset the screen-recording permission record after re-signing. Fully quit Codex.app, reopen it, and allow Screen & System Audio Recording in System Settings when prompted.

Target not found / version unsupported — do not continue, do not hand-patch. The build likely needs a new adaptation.

Plugins visible but a specific plugin is still unusable — run View current status first. On 26.429.20946, 26.429.30905, 26.429.61741, and 26.506.21252, Plugin install availability enabled means the top-level connector-unavailable install block is patched, and Plugin install modal content enabled means the empty install-modal detail card gate is patched. Remaining failures usually come from plugin state, connector runtime behavior, or admin-side restrictions.

GPT-5.5 visible but requests fail — the UI entry is present, but your custom API provider still needs to accept model: "gpt-5.5".

Codex.app won't open after an old broken run (left Resources/app behind or wrote a bad integrity hash):

1. Delete /Applications/Codex.app/Contents/Resources/app
2. Rename app.asar1 back to app.asar
3. Reopen Codex.app

License

MIT. See LICENSE.