Codex: Codex App Interface Guide
Last updated: 2026-08-31
The Codex App features a classic three-panel layout and offers the most complete feature set. This lesson covers each area in detail.
📋 Prerequisites: Codex App installed (see Lesson 2)
1. What You Will Learn
- Three-panel layout structure
- Left panel: task list functions
- Center panel: conversation window operations
- Right panel: multi-function area usage
2. Overall Layout
The Codex App uses a three-panel layout:
| Area | Position | Function |
|---|---|---|
| Task List | Left | Manage multiple parallel tasks |
| Conversation Window | Center | Primary interaction area with Codex |
| Multi-Function Area | Right | File browser, terminal, code viewer |
3. Left Panel: Task List
(1) Functions
- Create new tasks
- Switch between tasks
- View task status (in progress / completed / failed)
- Delete tasks
(2) Task Status
| Status | Icon | Description |
|---|---|---|
| Running | 🔄 | Codex is executing the task |
| Completed | ✅ | Task finished successfully |
| Awaiting confirmation | ⏸ | Needs an Approve action |
| Failed | ❌ | Execution error |
| Cancelled | ⏹ | Manually cancelled by user |
▶ Example 1: Alice Managing Parallel Tasks
TEXT
📖 Display only
Alice handles three tasks simultaneously:
🔄 Task 1: Refactor auth module
⏸ Task 2: Fix payment bug (awaiting confirmation to delete file)
✅ Task 3: Add logging (completed)
Click Task 2 → Review operations in conversation window → Click Approve
4. Center Panel: Conversation Window
(1) Input Area
- Text input box: Enter task descriptions or append instructions
- Attachment button: Attach files or images as context
- Send button: Submit task
(2) Message Types
| Type | Description |
|---|---|
| User message | Your task description input |
| Codex reply | Codex's operation explanation and results |
| File modification | Displays code diff |
| Command execution | Displays shell command and output |
| Confirmation request | Operations requiring your Approve/Reject |
(3) Action Buttons
| Button | Description |
|---|---|
| Approve | Approve Codex's operation |
| Reject | Reject the operation |
| Edit | Modify Codex's proposed code |
| Retry | Have Codex try again |
▶ Example 2: Reviewing Code Changes
DIFF
--- a/src/auth/login.ts
+++ b/src/auth/login.ts
@@ -15,3 +15,8 @@
return jwt.sign(payload, secret);
+}
+
+export function verifyToken(token: string): JwtPayload {
+ return jwt.verify(token, secret) as JwtPayload;
}
[Approve] [Reject] [Edit]
5. Right Panel: Multi-Function Area
(1) File Browser
- Browse the project file tree
- See which files Codex has modified
- Click a file to view its content
(2) Terminal Panel
- View commands executed by Codex
- View command output
- Manually enter commands
(3) Code Viewer
- View full file contents
- View diff comparisons
- Syntax highlighting
(4) Context Panel
- View currently used context files
- Manually add/remove context
- View context window usage
6. Top Toolbar
| Feature | Description |
|---|---|
| Model selection | Switch the AI model in use |
| Sandbox mode | Switch between Suggest / Auto Edit / Full Auto |
| Project selection | Switch the current working project |
| Settings | Open the settings panel |
7. Keyboard Shortcuts
| Shortcut | Function |
|---|---|
Cmd/Ctrl+N |
New task |
Cmd/Ctrl+Enter |
Send message |
Cmd/Ctrl+Shift+A |
Approve all |
Cmd/Ctrl+Shift+R |
Reject all |
Cmd/Ctrl+1/2/3 |
Switch right panel |
Cmd/Ctrl+. |
Interrupt current task |
8. Settings Panel
| Setting | Description | Default |
|---|---|---|
| Sandbox mode | Suggest / Auto Edit / Full Auto | Suggest |
| Default model | AI model selection | gpt-5-codex |
| Auto-save | Automatically save Codex modifications | On |
| Theme | Dark / Light | Follow system |
| Font size | Code font size | 14px |
❓ FAQ
Q Can I run multiple tasks at the same time?
A Yes. Codex App supports multi-task parallelism — each task runs in an independent sandbox without interference.
Q Can I resize the conversation window?
A Yes — drag panel borders to adjust area sizes. You can also collapse the left or right panel.
Q Where can I view files modified by Codex?
A The file browser on the right marks modified files — click to view the diff. The conversation window also shows each modification in real time.
Q Are the App and CLI features the same?
A Core features are the same. The App offers a richer GUI experience (file browser, multi-task management), while CLI is better for terminal users and automation scenarios.
Q How do I stop a running task?
A Right-click the task in the task list and select Cancel, or use the shortcut Cmd/Ctrl+.
📖 Summary
- Three-panel layout: task list + conversation window + multi-function area
- Left panel manages parallel tasks; center panel interacts with Codex
- Right panel views files, terminal, and code changes
- Master keyboard shortcuts for improved efficiency
- Settings panel controls sandbox mode, model, and more
📝 Exercises
- Basic (⭐): Create and complete a simple task in the Codex App. Take screenshots of each area.
- Intermediate (⭐⭐): Run two tasks simultaneously and observe parallel execution. Record task status changes.
- Advanced (⭐⭐⭐): Customize the Codex App settings to find your optimal configuration and explain your choices.
