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Codex Command MasterLabels and command selectionHow to read a detail guideComplete command listTerminal CLI Commands and Options

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Conversation and context

Cmd. /clearCmd. /renameCmd. /archiveCmd. /deleteCmd. /compactCmd. /copyCmd. /memoriesCmd. /importCmd. /initCmd. /mentionCmd. /forkCmd. /sideCmd. /resumeCmd. /newCmd. /cdCmd. /exportCmd. /recap

Planning and execution

Cmd. /planCmd. /goalCmd. /psCmd. /stopCmd. /app

Review and verification

Cmd. /review

Models and settings

Cmd. /modelCmd. /fast

Permissions and integrations

Cmd. /permissionsCmd. /ideCmd. /setup-default-sandboxCmd. /sandbox-add-read-dirCmd. /pluginsCmd. /hooksCmd. /approveCmd. /skillsCmd. /mcp

Status and diagnostics

Cmd. /agentCmd. /appsCmd. /diffCmd. /feedbackCmd. /personalityCmd. /rawCmd. /statusCmd. /debug-configCmd. /title

Display and input

Cmd. /keymapCmd. /vimCmd. /experimentalCmd. /statuslineCmd. /themeCmd. /petsCmd. /voiceCmd. /worktree

Account and usage

Cmd. /exitCmd. /logoutCmd. /quitCmd. /usage

Legacy

Cmd. /approvals

Verification and history

Current verification scopeHandbook updatesRelease coverage historyEarlier verification recordsCommand change history
Handbook›Codex Command Master›Cmd. /fast
한국어English

Cmd. /fast

Turn Fast mode on or off, or report its status, to change the service tier without changing reasoning effort.

Key takeaways

  • Turn Fast mode on or off, or report its status, to change the service tier without changing reasoning effort.
  • Check the input surface and availability before using the examples below.

Purpose

Turn Fast mode on or off, or report its status, to change the service tier without changing reasoning effort.

/fast

Availability

FieldValue
Input surfaceRunning CLI prompt
KindBuilt-in
StatusConditional
Aliases—
Documented minimumNot specified
Reviewed against2026-09-22 · Codex CLI 0.155.1

Requires Fast support in the model catalog; check credit usage for the selected service tier.

Examples

/fast

When to use it

  1. Use /fast on when faster responses justify increased credit consumption.
  2. Use /fast off to switch back, and /fast status to verify the setting.

Choosing related commands

CommandDifferenceChoose It When
/fastChanges Fast/Standard service behaviorYou want speed control without changing model family
/modelChanges the active modelYou need a different model
/statuslineDisplays footer statusYou want Fast state visible all the time

Effects and persistence

Switches the supported model's fast processing path. It is separate from reasoning effort and may have different billing or quota rules.

/fast turns Fast mode on or off, or reports the current Fast mode status.

Cautions

  • The command is visible only when the active model catalog offers a Fast tier.
  • Document when the team expects Fast mode to be allowed.

Official sources

  • Developer Commands
  • Releases
  • Speed

Complete command list · Verification scope · History for this command

Related docs

Cmd. /fast

Claude Code Command Master · Switches the supported model's fast processing path. It is separate from reasoning effort and may have different billing or quota rules.

Cmd. /effort

Claude Code Command Master · Set or inspect model-specific reasoning effort.

Cmd. /statusline

Configure TUI footer status-line fields.

Session Command Group

Commands for keeping long Codex sessions continuous and readable.

Cmd. /release-notes

Claude Code Command Master · Displays selected release notes in the transcript without adding them to model conversation context.

Cmd. /model

Switch among GPT-6 Astra, GPT-5.6 Sol, Terra, Luna, and supported reasoning effort levels.

Cmd. /permissions

Change Codex approval and permission policy during a session.

On this page

PurposeAvailabilityExamplesWhen to use itChoosing related commandsEffects and persistenceCautionsOfficial sources