CLAUDE_AX_STARTUP_QUIET_MS

Updated October 13, 2026 by Alex Sorokoletov

CLAUDE_AX_STARTUP_QUIET_MS is a Claude Code environment variable: Startup quiet window (milliseconds) for screen-reader mode. First shipped v2.1.217; the changelog names the fix but not the knob. Added between v2.1.215 and v2.1.217 and still present in v2.1.294. It is listed in the official reference.

Status	Present in v2.1.294
Added	Added between v2.1.215 and v2.1.217
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_AX_STARTUP_QUIET_MS=<value>
claude

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

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

Release notes that mention it

claude-code-env-vars-v2-1-217

Related variables

CLAUDE_AX_PREPARK_MS
CLAUDE_AX_SCREEN_READER
CLAUDE_CODE_ACCESSIBILITY: Enable accessibility mode; disables cursor hiding.
CLAUDE_CODE_ALT_SCREEN_FULL_REPAINT
CLAUDE_CODE_BLOCKING_LIMIT_OVERRIDE: Override token limit for input blocking.
CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN: Prevents the TUI from using the terminal alternate screen buffer.
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.

Frequently asked questions

What does CLAUDE_AX_STARTUP_QUIET_MS do?

Startup quiet window (milliseconds) for screen-reader mode. First shipped v2.1.217; the changelog names the fix but not the knob.

Which Claude Code version has CLAUDE_AX_STARTUP_QUIET_MS?

Added between v2.1.215 and v2.1.217 and still present in v2.1.294.

How do I set CLAUDE_AX_STARTUP_QUIET_MS?

Export it before starting Claude Code (export CLAUDE_AX_STARTUP_QUIET_MS=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.