CLI and Slash Command Tips

You open a terminal, type codex "fix the bug", and wait. It works, but it is the slowest way to use the CLI. Power users chain sessions, pipe structured output, fork conversations when they hit a dead end, and use slash commands to trigger code reviews without leaving the TUI. The Codex CLI is a full development environment disguised as a single binary.

What You’ll Walk Away With

• Session management patterns that eliminate context re-entry
• Slash commands for review, permissions, and model switching
• Image input techniques for visual debugging from the terminal
• Scripting patterns with codex exec for automation
• Keyboard shortcuts and TUI tricks that save time on every turn

Session Management

Resume Instead of Re-explaining

The most common CLI waste is re-explaining context. Use resume instead:

# Resume the most recent session
codex resume --last

# Resume from any directory (not just the current one)
codex resume --last --all

# Resume a specific session by ID
codex resume abc12345-...

# Resume and immediately give a follow-up instruction
codex resume --last "The approach we discussed works. Implement it and run tests."

The resumed session carries over the entire transcript, so Codex remembers every decision, constraint, and file it touched.

Fork When You Want to Explore

Want to try an alternative approach without losing your current conversation?

# Fork the most recent session
codex fork --last

# Fork a specific session
codex fork abc12345-...

This creates a new thread with the full transcript of your previous session. You can branch the conversation in a different direction while the original stays intact.

Prompt: Fork and compare approaches

Start a session:

codex "Propose two approaches for implementing caching in our API service"

Then fork and explore each:

codex fork --last "Implement approach 1: Redis-based caching"
# In a separate terminal:
codex resume --last "Implement approach 2: In-memory LRU cache"

Compare the results from both forks.

Non-Interactive Resume

Resume works with codex exec too, so you can continue automated sessions:

# Continue the last exec session with new instructions
codex exec resume --last "Fix the race conditions you found"

# Resume a specific exec session
codex exec resume abc12345-... "Implement the plan"

Slash Commands

Built-In Commands

Type these inside the interactive TUI:

Command	What It Does
/review	Open the code review menu
/fork	Fork the current session
/model	Switch the model mid-session
/permissions	Change approval mode without restarting
/status	Check remaining context, credits, and loaded files
/exit	Close the session
/feedback	Submit feedback to OpenAI
/skills	Browse and invoke available skills
/compact	Manually trigger context compaction

Code Review with /review

/review opens a menu with four presets:

1. Review against a base branch — Diffs your work against the upstream merge base
2. Review uncommitted changes — Inspects staged, unstaged, and untracked files
3. Review a commit — Picks a recent commit and analyzes the exact changeset
4. Custom review instructions — Your own prompt (e.g., “Focus on accessibility regressions”)

The review runs as a read-only pass and reports findings without modifying files. Set a dedicated review model in config:

review_model = "gpt-5.3-codex"

Permission Switching with /permissions

You started in read-only mode but now trust the agent enough for full auto? Switch without restarting:

/permissions

Choose between Auto, Read-only, and Full Access mid-session.

Keyboard Shortcuts in the TUI

Shortcut	What It Does
@	Fuzzy file search — drop a path into your message
!	Run a local shell command inline
Enter (while running)	Inject instructions into the current turn
Tab (while running)	Queue a follow-up for the next turn
Esc (2x)	Edit your previous message
Esc (repeated)	Walk back through earlier messages to fork from any point
Ctrl + G	Open your $VISUAL editor for composing long prompts
Ctrl + C	Cancel the current operation

The @ File Reference

Type @ in the composer and a fuzzy file search opens over your workspace. Press Tab or Enter to drop the path into your message. This is faster than typing paths manually and ensures accuracy.

The ! Shell Command

Prefix a line with ! to run a shell command without leaving the TUI:

!git log --oneline -5
!npm test -- --filter=auth
!cat src/routes/users.ts | head -20

Codex treats the output as context for your next prompt. Useful for feeding error messages, test output, or file contents directly into the conversation.

The Ctrl+G Editor

For long, multi-paragraph prompts, press Ctrl + G to open your configured editor ($VISUAL or $EDITOR). Write the prompt in your editor, save and close, and Codex sends it.

Prompt: Efficient CLI debugging workflow

# Start with an error
codex "Here's a test failure from our CI:
$(npm test -- --filter=payments 2>&1 | tail -30)
Find the root cause and fix it."

# If the fix works but introduces a regression:
codex resume --last "The fix works for payments but breaks the auth tests. Fix both without reverting."

The resume carries over the full debugging context.

Image Inputs

From the Command Line

# Single image
codex -i screenshot.png "This screenshot shows a broken layout. Fix the CSS."

# Multiple images
codex --image before.png,after.png "The first image is correct. The second shows a regression. Find what changed."

In the Interactive TUI

Paste images directly into the composer. On macOS, you can screenshot with Cmd + Shift + 4 and paste the clipboard image.

Scripting with codex exec

Basic Automation

# Non-interactive task
codex exec --full-auto "Fix the failing linter warnings and run the tests"

# With structured JSON output
codex exec --json --full-auto "Analyze the test coverage" 2>/dev/null | jq '.item.text'

# Pipe prompt from stdin
echo "Explain the auth middleware in src/middleware/auth.ts" | codex exec -

Structured Output with Schemas

Force Codex to return data in a specific format:

codex exec --output-schema schema.json --full-auto "List all API endpoints with their HTTP methods and paths"

Where schema.json defines the expected shape:

{
  "type": "object",
  "properties": {
    "endpoints": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "method": { "type": "string" },
          "path": { "type": "string" },
          "description": { "type": "string" }
        }
      }
    }
  }
}

Save the Final Message

codex exec --output-last-message result.md --full-auto "Generate a changelog for the last 10 commits"

The agent’s final response is written to result.md for downstream processing.

Working Directory Tips

Start From Any Directory

# Set the working root without cd
codex --cd /path/to/project "Analyze the codebase"

# Grant write access to additional directories
codex --cd apps/frontend --add-dir ../backend --add-dir ../shared "Coordinate changes across frontend and backend"

Skip Git Repo Check

For one-off tasks outside a Git repository:

codex exec --skip-git-repo-check "Generate a Python script that parses CSV files"

Cloud Tasks from the CLI

# Interactive picker for cloud tasks
codex cloud

# Submit a task directly
codex cloud exec --env my-env-id "Run the full integration test suite and fix any failures"

# Submit with best-of-N attempts
codex cloud exec --env my-env-id --attempts 3 "Implement the caching layer"

# List recent cloud tasks
codex cloud list --json | jq '.tasks[] | {id, status, title}'

# Apply a cloud task's diff locally
codex apply TASK_ID

When This Breaks

• Session resume shows wrong context: Sessions are scoped to the working directory by default. Use --all to find sessions from other directories.
• Shell completions not appearing: Ensure the eval line is after compinit in your shell config. Restart your shell.
• codex exec hangs: The agent may be waiting for approval. Add --full-auto or --ask-for-approval on-request to avoid interactive prompts in non-interactive mode.
• Image input rejected: Codex accepts PNG and JPEG. Other formats may not be supported. Convert with convert input.webp output.png before attaching.
• ! command blocked: The sandbox still applies to inline shell commands. If the command needs write access or network, adjust your sandbox mode.

What’s Next

• Cloud Workflows — Deep dive into cloud task patterns
• App Features — Visual workflows that complement the CLI
• Advanced Techniques — Power user patterns across surfaces