CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN

Updated October 13, 2026 by Alex Sorokoletov

CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN is a Claude Code environment variable: Prevents the TUI from using the terminal alternate screen buffer. If Claude Code's UI is eating your terminal history, breaking tmux scrollback, or failing in CI log capture — this flag keeps output in the primary buffer. Added between v2.1.128 and v2.1.138 and still present in v2.1.294. It is listed in the official reference.

Status	Present in v2.1.294
Added	Added between v2.1.128 and v2.1.138
Category	Terminal and UI
Official docs	Listed

How to set it

For one session, export it in the shell that starts Claude Code:

export CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN=<value>
claude

To apply it to every session, add it to the env object of a settings file:

// ~/.claude/settings.json
{
  "env": {
    "CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN": "<value>"
  }
}

Release notes that mention it

Claude Code v2.1.143 — 27 New Env Vars, /goal, Agent View, and a Free Model Upgrade

Related variables

CLAUDE_AX_SCREEN_READER
CLAUDE_CODE_ALT_SCREEN_FULL_REPAINT
CLAUDE_CODE_DISABLE_MOUSE: Disables all mouse input handling in the terminal UI.
CLAUDE_CODE_DISABLE_MOUSE_CLICKS: Granular mouse click disable, added in v2.1.88.
CLAUDE_CODE_DISABLE_TERMINAL_TITLE: Stop Claude Code from setting the terminal title.
CLAUDE_CODE_DISABLE_VIRTUAL_SCROLL: Disable virtual scrolling in terminal UI.
CLAUDE_RUNNER_DISABLE_AWAITING_ACTION_OVERRIDE
CLAUDE_AX_PREPARK_MS

Frequently asked questions

What does CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN do?

Prevents the TUI from using the terminal alternate screen buffer. If Claude Code's UI is eating your terminal history, breaking tmux scrollback, or failing in CI log capture — this flag keeps output in the primary buffer.

Which Claude Code version has CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN?

Added between v2.1.128 and v2.1.138 and still present in v2.1.294.

How do I set CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN?

Export it before starting Claude Code (export CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN=value), or add it to the "env" object in ~/.claude/settings.json to apply it to every session.

All variables, searchable: Claude Code environment variables.